Huge projects almost inevitably cause controversy somewhere, but some cause more than most. Overspending, underdelivering and detrimental environmental impact are just some of the problems that have plagued these big builds. Click or scroll through to discover the world’s most controversial megaprojects. All dollar amounts in US dollars unless otherwise stated.

A boundary between the US and Mexico has existed since 1853, but really became controversial following the election of Donald Trump in 2016. Various administrations had already installed 654 miles (1,052km) of fences and barriers, but Trump promised to build a wall that would reach 1,000 miles (1,609km) in length during his time in office as part of his stringent anti-immigration policy. The former president said the project would cost between $8 billion and $12 billion (£5.8bn-£8.7bn) and insisted that Mexico would be the ones to foot the bill. 

The project was not only overbudget, but the $15 billion (£10.9bn) eventually spent on construction was financed by funds taken from US counter-drug budgets and military construction funding. Mexico did not contribute a single dollar to the work. As of January 2021, the Trump administration had installed 452 miles (727km) of wall, but only 47 miles (75.6km) of that stretch were built from scratch – the rest was reconstruction of previously existing barriers. President Biden will not be picking up from where the Trump administration left off, having promised not to construct “another foot” of the wall while in office, although he has said he will not deconstruct any part of the existing wall. This pledge will make him the first president since George H. W. Bush not to add to the barrier and will leave this controversial US megaproject incomplete for at least another four years.

The St Francis Dam, which was located in the San Francisquito Canyon around 40 miles (64km) from downtown Los Angeles, was constructed between 1924 and 1926. The dam made up a key part of the Los Angeles Aqueduct, which was the city's main source of water. That was until 12 March 1928 when the dam collapsed and killed hundreds of people.

The brainchild of self-taught civil engineer William Mulholland, the dam was an accident waiting to happen. A multitude of engineering defects destabilised the structure, which was built on shaky foundations in an area with thoroughly unsuitable geology for such a substantial piece of infrastructure. Mulholland was cleared of any wrongdoing but the catastrophic collapse put an abrupt end to his formerly illustrious career.

Montreal’s ‘Big O’ stadium was quickly renamed the ‘Big Owe’ due to the building coming in at 13 times the original cost estimate. There was a manic scramble to get it finished in time for the Games on 17 July 1976, with 3,000 staff working 24 hours a day in the final months, and even then it wasn't quite finished in time. Construction workers still finishing up reportedly got in the way of the first athletes coming into the stadium for the opening ceremony.

During the build, architect Roger Taillibert and Montreal's mayor Jean Drapeau, who had commissioned the stadium, faced multiple major obstacles. There were several labour strikes that wiped 30% off the available work time, a tripling of the price of structural steel to contend with, as well as corruption among officials. Three decades later, CBC reported that the $1.5 billion debt – the equivalent of $6.8 billion (£5bn) in today’s money – from the 1976 Summer Games had finally been cleared.

In 1990 the legendary Hubble Space Telescope was launched into orbit, 353 miles (568km) above Earth. At the time, the BBC reported how the Hubble would provoke “a drastic revision of the shapes, sizes and content of galaxies” – having already drastically revised its budget and deadline for launch. The Hubble took 20 years to build, which was at least seven years longer than planned. Plus, it cost three times the original estimate, coming in at $1.5 billion at the time, which is the equivalent of $2.9 billion (£2.4bn) in today's money.

Despite the cost, technical problems materialised even after the launch, including the malfunctioning of the solar panels that powered the telescope and flaws in the mirrors that help produce images. This year NASA is due to launch the Hubble's successor: a new and improved, long-distance, high-resolution space telescope called the James Webb Space Telescope. However, the project is already following in its predecessor’s footsteps. After being announced in 1996, it was set to launch in 2007 at a cost of $1 billion. The cost has since mushroomed to $8.8 billion (£6.5bn), and its new launch date was meant to be March 2021. But that's already been pushed to October 2021 as a result of the coronavirus pandemic.

When Denver’s new airport was finally complete, 16 months late, in 1995 it was hailed as an economic catalyst by advocates and a legally dubious, colossal waste of money by critics. The New York Times reported that the project had cost $4.9 billion by its completion, equivalent to $8.2 billion (£6.8bn) in today's money. This made it three times overbudget, which led to the project's own financers filing suits. 

Multiple setbacks to planning and construction were responsible for the enormous overspends. Perhaps the single most costly failure was, ironically, the airport’s key selling point – an ultra-modern, fully-automated baggage system. It initially malfunctioned and shredded bags, costing more than $100 million – equivalent to $397 million (£289m) today – to get into working order. Since then, the airport has been the subject of a host of conspiracy theories, from the hypothesis that markings on the airport floor are satanic symbols, to the idea that its underground bunkers might be a secret lair.

The most expensive US highway megaproject on a cost-per-mile basis, Interstate H-3, which cuts through the Hawaiian island of O'ahu, has a hugely problematic and controversial history. Originally proposed in the early 1960s, the highway was strongly opposed by many Native Hawaiians.

The megaproject didn't commence until the late 1980s with protests, environmental complaints and legal challenges significantly delaying its completion. Costing a budget-busting $1.3 billion, which is equivalent to $2 billion (£1.7bn) today, the highway eventually opened in 1997, but to this day local opposition remains strong and many Native Hawaiians refuse to use it as they believe it's cursed. The 15-mile freeway was shut for several days in September as the stretch was transformed into a mass testing site for COVID-19, but even this was controversial as local highway authorities objected to the road being used for this purpose.

Nicknamed “the Desertron”, the Superconducting Supercollider (SSC) was a proposed particle accelerator complex in Texas that would have been the most powerful of its kind in the world. Initially, it was meant to be America's answer to the famous Large Hadron Collider (LHC) in Switzerland that was completed in 2008.

Preliminary work on the SSC began in the late 1980s, and by the early 1990s around 15 miles of tunnels were bored and 17 shafts sunk on the site. Then Congress pulled the plug. The budget had surged from $4.4 billion to more than $11 billion and the megaproject was deemed to have been grossly mismanaged. All in all, a painful $2 billion of US taxpayers' cash, equivalent to roughly $3.7 billion (£3bn) today, was wasted on the project.

An arduous 15 years in the making, the Big Dig turned out to be America's most troubled highway megaproject and the priciest overall. Pretty much everything that could have gone wrong did go wrong. The megaproject involved redirecting the highway that passes through the centre of Boston into a 3.5-mile (5.6km) tunnel, and called for the construction of additional tunnels and a bridge.

A major headache for Bostonians who had to endure years of severe disruption during the build, the Big Dig, which eventually cost almost $15 billion (£9.7bn), kicked off in 1992. From the get-go, it was dogged by a plethora of problems that included budget overruns, long delays, design flaws, shoddy workmanship, and accusations of negligence.

Construction of the 5.4-mile (8.7km) Hallandsås Rail Tunnel (also known as Scanlink) in southwestern Sweden began in 1992 and was expected to have been fully completed by 1995. Almost from the beginning, groundwater began seeping into the tunnel, presenting a massive problem for engineers working on the megaproject. Compounding the issue, the drill broke down after boring just 59 feet (18m) of rock.

Adding to the drama, the principal contractor went bust and the megaproject was taken over by construction titan Skansa, which used a toxic substance called Rhoca-Gil to seal cracks in the rock that ended up poisoning fish and cattle in the vicinity. Works were halted in 1997 and didn't resume again until 2005. The tunnel was finally finished in 2015, 23 years behind schedule and hugely over-budget, costing a total of $1.3 billion (£946m).

A project that’s been mired in controversy from the get-go, the idea for the Three Gorges Dam on the Yangtze River, China, was proposed in 1919 by politician Sun Yat-Sen. But it wasn’t until the mid-1950s that the idea was given serious attention, and due to the Chinese civil war building work didn’t start until 1994. The largest hydroelectric power plant in the world, it was built by 40,000 workers over the course of 12 years. The dam was the subject of social media rumours last year, with images circulating that showed the dam apparently at risk of collapse and cities overcome with flooding, but officials denied the claims.

During its construction the project wasn’t short of critics either. Damaging ecosystems and displacing 1.2 million people, as well as submerging entire villages in order to be built, before and after pictures such as these show the dramatic change in the landscape it has caused. Plus, the project cost more than four times the original budget of $8.35 billion, with a reported final budget of $37.23 billion in 2009, the equivalent of $44.9 billion (£32.7bn) in today’s money.

Built to be the pride of Scotland, this project was completed in 2004, which was three years late and at a total cost of £414 million, which would be £650 million ($893m) in today's money, making it 10 times over budget. To add insult to injury, reports have since suggested that the building may only have a remaining "estimated useful life" of another 40 years or so, meaning that by 2060 it may need a massive refit.

Designed by Spanish architect Enric Miralles, the project was rife with controversy. Lord Fraser of Carmyllie, a prominent Scottish politician, launched a public inquiry into the construction in 2004. His conclusions were that the handling of construction, by everyone from consultants to contractors and members of the Scottish parliament, ought to have been better managed in order to avoid the massive costs and delays. Despite criticisms, the unusual building has attracted critical acclaim for its architecture, and it was awarded the 2005 Stirling Prize for the best building in the UK.

A monument to the hubris that characterised Spain's pre-financial crisis spending spree, Ciudad Real Central Airport was marred by poor planning from the outset. Originally envisaged as an overflow airport for Madrid, the €1 billion ($1.2bn/£881m) so-called 'central' airport was in reality built in the middle of nowhere, 141 miles away from the Spanish capital.

The white elephant, which was planned to handle up to 10 million passengers a year, opened in 2008 but attracted only three low-cost airlines and just several thousand travellers in the first 12 months. In 2012, the airport's owner went bust and all operations ceased. The site was eventually sold in 2015 to a Chinese-led consortium of investors for a measly €10,000 ($12.1k/£8.8k). Three years later it was sold on for €56.2 million ($68.1m/£49.6m) to Ciudad Real International Airport SL and in 2019 even received its first flight, although it had no passengers. After a failed rebranding as Madrid Airport South, it has been suggested that the "ghost airport" may be used for flight training and tech support, but for now it remains abandoned.

During the early 2000s economic boom in Spain, Galicia’s former leader Manuel Fraga set out to build a sprawling complex of six buildings dedicated to showcasing Galician culture. He enlisted the help of American architect Peter Eisenman and set a budget of €129 million for the entire build, the equivalent of $214 million (£156m) today. In 2011 when it was still only half-built, it was reported that the building had already cost more than triple that, at €400 million ($484m/£353m).

Galicia's flagship cultural project now comprises four large empty buildings and two big holes in the ground. In 2013, Spanish newspaper El País estimated that the complex would set Spanish taxpayers back at least another €170 million ($206m/£150m), making it simply unaffordable in a time of austerity. With the upkeep and millions more dollars haemorrhaged on unpopular exhibitions, the Galician government decided to end work and so the project remains incomplete. 

The biggest and most costly failed IT megaproject of all time, the NHS National Programme for IT (NPfIT) was an attempt by the UK's Department of Health to unite all public patient records in a single user-friendly system, linking 30,000 doctors to 300 hospitals. Work commenced in 2002 on the vast centralised database, which was estimated to cost £2.3 billion – the equivalent of £3.5 billion ($4.8bn) today – and was due for completion in 2005.

In reality, the megaproject was badly managed and plagued by technical issues, changing specifications, privacy controversies, supplier problems and a whole lot more besides. Unfit for purpose and unfinished in 2011, the projected completion cost had mushroomed to £12.7 billion ($17.4bn), prompting the government to kill the NPfIT. The failed project cost UK taxpayers £10 billion ($13.7bn).

In what turned out to be the most expensive public works megaproject in Californian history, the replacement of the seismically unsound eastern section of the San Francisco-Oakland Bay Bridge was no mean feat. Work began in 2002 on the earthquake-proof structure, which was scheduled for completion in 2008 and projected to cost $2.6 billion – the equivalent of $3.1 billion (£2.3bn) in today’s money – up from an estimate of $1 billion six years earlier.

All sorts of problems arose during the build including design defects, water leaks, bolt failures and a welding controversy that led to an FBI investigation. Unsurprisingly, the seemingly endless string of issues delayed the project and bumped up the budget considerably. Ultimately, the replacement span opened to traffic in 2013, five years behind schedule, with the final bill coming in at a hefty $6.4 billion (£5.2bn).

Dubbed “Dubai's ultimate folly” by Guardian journalist Oliver Wainwright, The World was unveiled to much fanfare in May 2003. Work began that same year on the ambitious archipelago of 300 artificial islands off the coast of the Emirate, but came grinding to a halt in 2008, due to the global financial crisis and collapse of the Dubai property market. Investors found themselves seriously out of pocket. 

The owner of Great Britain Island was jailed for fraud, while Ireland's proprietor took his own life. In 2009, reports suggested several islands were sinking into the sea. Lebanon was the only developed island until construction began in 2019 on the $5 billion (£4.1bn) Heart of Europe, a six-island development that was expected to open by the end of 2020. Although work on the project has continued throughout the COVID-19 outbreak, there has been no confirmation of the islands' opening and welcoming visitors just yet. The majority of islands remain untouched and doubts persist over whether the entire megaproject will ever be completed.

Built on the site of the former World Trade Center in New York, the Oculus transit hub was designed to replace the destroyed Port Authority Trans-Hudson (PATH) station, as well as serving as a memorial to the 3,000 people who lost their lives in the 9/11 attacks. While it’s been praised for its cutting-edge architectural design – with wing-like roof panels evoking a dove in flight – not everyone has been pleased with the project.

It was opened to the public in 2016, seven years behind schedule. Not only that, it came at a total cost of $4 billion (£2.9bn), double the original estimate. Former New York Governor George Pataki had insisted on keeping the No. 1 subway line open during construction, which had added $355 million (£259m) to the costs, plus the Port Authority in charge of the project had rejected around half a million dollars in potential savings. The expenses didn’t stop with the project’s completion either, and in 2019 more than $250,000 (£182k) was spent on repairing the Center’s leaky skylight. 

First proposed back in 2002, the American Dream Meadowlands Mall in New Jersey (formerly known as the Xanadu project) quickly turned into an American nightmare. Beset by everything from investor bankruptcies and legal challenges to ballooning costs and construction delays, the sprawling retail and entertainment complex was initially slated to cost $1.2 billion (£876m) and open in 2007. The cost is now expected to come in at $5 billion (£3.8bn).

Construction of the East Rutherford mall began in March 2005 but the opening date was pushed back and the mall's parent company ended up going bust in 2007. A slew of badly executed hand-offs, bankruptcies, litigation and countless other issues, including the partial collapse of the roof, have further delayed the megaproject, which finally started to open its doors in October 2019. More than 16 years after construction began and currently trying to operate in the midst of a pandemic, the mall has yet to fully open and much of the project is still a work in progress. 

The Expeditionary Combat Support System (ECSS) was meant to save money, yet it ended up costing US taxpayers $1.1 billion (£899m) and pretty much flopped. Designed by the US Air Force, it was essentially intended to streamline the process by which the supply chain is managed.

Development was contracted out in 2005 to Oracle and was later taken over by the Computer Sciences Corporation. Despite the enormous funds that were ploughed into the project, the US Air Force concluded in 2012 that the system was more or less useless and canned the entire thing. Senators Carl Levin and John McCain described it as “one of the most egregious examples of mismanagement in recent memory”.

Planning for a new airport for Berlin started in 1989 but the megaproject wasn't approved until 2006. So much for Teutonic efficiency. Construction began that same year and the airport was poised to open in October 2011. All in all, it was expected to cost €2.4 billion ($2.9bn/£2.1bn), but the budget and scheduled completion date proved be to be very wishful thinking indeed.

In summer 2010 the opening date was pushed back to June 2012. An embarrassing catalogue of errors, from incorrectly-sized escalators to a shortage of check-in desks, further delayed the project and skyrocketed the budget to more than €7 billion ($8.2bn/£6.3bn). Incredibly, as the demand for air travel collapsed in the wake of the coronavirus pandemic, the airport has finally been finished and opened to passengers in November 2020. However, Terminal 2 will not open until later this year due to travel restrictions and decimated passenger numbers grounding hundreds of flights.

Construction began on a new state-of-the-art reactor at the Flamanville Nuclear Power Plant in northern France in 2007. French energy giant EDF budgeted €3.3 billion – the equivalent of $4.8 billion (£3.5bn) today – for the flagship megaproject and proudly announced that it would take just four and a half years to complete, aiming for it to be fully operational in 2012.

But the reactor is still unfinished. Setback after setback, including problems with welding, issues with the strength of the steel used and even an explosion on the site, have delayed the project spectacularly and sent costs soaring. Unit 3 isn't expected to get up and running until 2024 at the earliest, over a decade late, and the costs have now skyrocketed to €12.4 billion ($14.6bn/£11.2bn).

Why did the Sochi Olympics cost 325% more than budgeted, setting Russian taxpayers back $51 billion (£42.2bn)? In a word: corruption. This was the most expensive – and controversial – Olympics in history due to corruption being endemic in the Russian construction industry. Two members of the opposition party, Leonid Martynyuk and Boris Nemtsov, claimed in a 2013 report that up to $30 billion (£24.8bn) of the budget had gone missing in "kickbacks and embezzlement" to President Putin's close associates. 

Although the project was technically finished on time, it came at a high cost to the workers. Human Rights Watch reported that some 16,000 migrant workers were employed on the project, working 12-hour shifts, seven days a week under immense pressure to get it finished in time, often being paid as little as $1.80 (£1.50) an hour. What's more, some other infrastructure remained unfinished at the start of the Games, including hotels without lobbies, working elevators or running water.

When the UK capital's Crossrail project launched with the catchphrase "on time and on budget" it was setting itself up for trouble, particularly as its budget was already a contentious issue for the nation’s government. This ongoing megaproject is now running almost £4 billion ($5.5bn) overbudget, with a staggering final bill estimated to be up to £18.7 billion ($25.6bn). The 60-mile (97km) rail line is designed to connect Reading and Heathrow in the west, and Shenfield and Abbey Wood in the east, to central London. 

A phrase that many UK rail passengers may be familiar with, the project has been delayed due to signalling issues. The dynamic testing, which is required to check if signals work, has taken longer than expected, plus the new stations along the route are all incomplete. As with many of the world’s megaprojects, work on Crossrail was temporarily suspended because of the COVID-19 outbreak. It was originally scheduled to open in December 2018 but, after multiple push-backs, the central section is now set to be up and running by 2022.

Three years before the opening game of the 2014 soccer World Cup in Brazil, the new São Paulo stadium set to host the match hadn't left the drawing board. Fast-forward to 1 June 2014, 11 days before the World Cup's opening match was due to kick off, and the Arena Corinthians was reportedly only able to be filled to three-quarters of its capacity for the final test match, with two temporary seating areas unfinished.

Brazil spent $15 billion (£12.4bn) on the 2014 World Cup in total, including $3 billion (£2.5bn) on new and refurbished stadiums, which was three times the budget. Up to 90% of the money for the stadiums came from the public purse, despite former president Lula da Silva’s promise that all stadiums would be privately financed. Droves of angry people took to the streets in Brazil’s major cities protesting that the billions used to fund the event would have been better spent on the country’s depleted healthcare and education systems. While the stadiums were finished on time, only six of the 35 promised public transportation projects were completed to schedule. 

The Keystone Pipeline System has transported oil from Alberta, Canada to Illinois and Texas in the US since 2010, but a proposed expansion, Keystone XL, has been a sticky subject for the two countries. In 2015 the fourth phase of the pipeline, which would run from Alberta to Nebraska, was vetoed by President Obama based on its environmental impact, but the project was then granted the go-ahead by his successor Donald Trump in 2019. Protests against the expansion continued and it wasn't long before it ran aground yet again…

President Biden revoked the permit mere hours after his inauguration on 20 January 2021, again on the basis of the proposed expansion’s environmental impact. In response, Alberta Premier Jason Kenney said that the move would put people out of work and weaken the US-Canada relationship. The project was set to cost around $8 billion (£5.8bn), which would have been privately funded, but it won't happen, for the duration of Joe Biden’s presidency at least.

The largest redevelopment project in the US West Coast city since the 1906 earthquake, the Hunters Point Naval Shipyard revamp in San Francisco was set to boast 12,000 relatively affordable homes and an array of shops, offices, restaurants and green spaces. Scheduled for completion sometime during the early 2030s, the waterfront development should have cost around $8 billion (£6.5bn).

Construction started in 2013 and several hundred condos were completed and sold before it was discovered that the site, which was used from the 1940s to the 1960s as a covert nuclear testing facility by the US military, showed dangerous levels of contamination. In 2018, the company in charge of the clean-up was alleged to have faked the soil tests that deemed the site toxin-free and documents from the US Environmental Protection Agency later showed that up to 97% of the samples were unreliable or falsified. On 1 January 2021, there were renewed calls for excavation of the site to stop, following a string of dust complaints as radioactive emissions continue to affect communities bordering the area. 

Nuclear projects seem to have a habit of over-promising and underdelivering. In 2008, utilities companies South Carolina Electric & Gas and Santee Cooper teamed up with the Westinghouse Electric Company to build two AP1000 nuclear reactors at South Carolina's Virgil C. Summer Nuclear Generating Station. Construction began in 2013 on the reactors, which were estimated to cost $11.5 billion (£9.3bn) and be operational by 2018.

Fabrication delays put back the megaproject's completion date to 2020 and costs soared. As a consequence, Westinghouse filed for Chapter 11 bankruptcy in March 2017 and the megaproject was eventually abandoned. A jaw-dropping $9 billion (£7.7bn) was wasted on the reactors. In September a deal was reached that allowed Santee Cooper to sell off the thousands of unused parts and equipment from the unfinished project.

Construction of Seattle's Alaskan Way Viaduct replacement tunnel, aka the Highway 99 tunnel, got underway in July 2013, and planners were confident the multibillion-dollar project would be done and dusted by December 2015. If only. In December 2013, Big Bertha, the enormous boring machine built specially for the vast megaproject, overheated and malfunctioned.

Big Bertha was eventually fixed in December 2015 and boring resumed, but a sinkhole that appeared on the site in January 2016 delayed the megaproject further. The tunnel finally opened to traffic in February 2019, three years and two months behind schedule and $600 million (£490m) overbudget. Ten months later the Washington State Department of Transportation won a $57.2 million (£41.6m) jury award after it sued Seattle Tunnel Partners for the cost of repairing Big Bertha and other damages that delayed the project.

Canada's most controversial megaproject, this enormous hydroelectricity venture in Labrador and Newfoundland has been nothing but trouble since construction began in 2013. Billed as an affordable and environmentally-friendly way to meet the energy needs of the two provinces, the megaproject is delayed and has blown the budget by quite a margin. Poor planning and botched engineering, among other issues, have pushed the scheme to CA$13.1 billion ($10.2bn/£7.5bn) – more than twice its original budget – and the discussion as to who is footing the bill is ongoing. 

Initially set for completion in 2017, the megaproject is already four years behind schedule. Parts are up and running, for example Nova Scotia Power customers have been paying for clean electricity from the project since 2018, but they only actually received power in December 2020. The supposedly green venture has also been blamed for flooding the area downstream of the Lower Churchill River and contaminating the watercourse with toxic methylmercury. The project is expected to be completed in the summer of 2021, but the coronavirus pandemic may delay the schedule even further.

The Nord Stream pipelines currently transport natural gas between western Russia and Germany, and they span approximately 761 miles (1,224km) through the Baltic Sea. The two pipelines went into service in 2011 and 2012, and Nord Stream is looking to double its transport powers by adding an additional two pipelines, known as Nord Stream 2. While some see the move as a sustainable way to ensure European energy security, others have been sceptical of the project in light of tensions between Russia and its Western neighbours.

Construction of Nord Stream 2 continues under a cloud of controversy, including a number of fines that have been issued to its leading company Gazprom by Polish watchdog UOKiK. The government agency slapped the company with a fine worth 29 billion złotys ($7.6bn/£5.9bn) in October for not securing Warsaw’s approval for the project, as well as dishing out hefty penalties to the five companies who are jointly financing the other half of the project. Gazprom has appealed the fine. The bulk of the first additional pipeline is set to be completed by June, but as members of the European Parliament have recently called for the entire project to be scrapped following Russia’s detention of Kremlin critic Alexei Navalny – to no avail –  Nord Stream 2 will likely be controversial right up until its completion.

Europe's most expensive megaproject, the UK's High Speed 2 network connecting London to Leeds will be built in two phases. The first phase linking London to Birmingham (pictured) is scheduled for completion by 2028-2031, while the second phase connecting the capital city to Manchester and Leeds isn’t scheduled to be ready until 2035-2040. The cost of the new network has gone up and up, with the most recent announcement suggesting that an additional £800 million ($1bn) would be needed to pay for asbestos removal and adding a new hub to London Euston station. 

It isn’t just the ballooning costs that make this railway line controversial, but also its possible impact on the English countryside. The Wildlife Trusts charity said that the infrastructure set to span England would make a “deep cut” across the landscape that could “stop nature’s recovery in its tracks”. The team behind HS2 has admitted the project will leave destruction in its wake, as almost 900 properties, 1,000 businesses and around 60 ancient woodlands will be destroyed during construction. The most recent protest action against the project saw nine activists dig their way into one of the tunnels close to London Euston station and occupy the space – eviction teams are still in the process of removing the protestors from the complex tunnel network.

Two of the world’s biggest mining groups, Rio Tinto and BHP, teamed up in 2001 to develop what would be North America’s largest copper mine. Planned for a site 60 miles (97km) east of Phoenix, Arizona, the deposit below the land is ample enough that it could provide a quarter of America’s demand for the metal but getting approval for the megaproject has been no easy ride. The site for the Resolution Copper mine is on sacred ground known as Oak Flat and is occupied by Apache Native Americans, who have strongly objected to the development based on the land's cultural and religious importance.

In 2014, President Obama signed a controversial bill that allowed BHP and Rio Tinto to exchange land it owned nearby for the land above the copper reserve. The bill came with the caveat that an environmental impact statement would be needed before the swap could go ahead, and this was published by the Trump administration in the former president’s final week in office. The battle is far from over though, as the local San Carlos Apache tribe, along with environmental groups, has said that it may pursue legal action to prevent the transfer of land. The tribe owned the land before the United States was founded and has lived on it for centuries, which caused disputes as to the land ownership. So far Rio and BHP have spent more than $2 billion (£1.5bn) on the project, but there may be a long way to go before any copper will be mined from the area.

Prince Mohammed Bin Salman of Saudi Arabia recently unveiled plans for The Line, a 100 mile-(170km)-long zero-carbon linear city that will make up part of the kingdom’s new $500 billion (£360bn) business zone. Called NEOM, which stands for “new future”, it's set to span a region across northwest Saudi Arabia, Jordan, and Egypt, and will run entirely on renewable energy when it is complete in 2030. The Line will be a car-free, walkable area, where inhabitants live within five minutes of all essential facilities. A crowning jewel in the “living laboratory” environment that developers are hoping to curate, The Line is one of several cities, ports and enterprise zones that the country hopes will house one million people on its completion.

The blueprint for The Line has been three years in the making and is set to cost between $100 billion and $200 billion (£72.8bn-£14.6bn). This seemingly idyllic project hasn’t been without its controversies, however. The al-Huwaitat tribe has lived on the proposed building plot for centuries, but some 20,000 members now face eviction to make room for the megaproject. There have also been reports of abduction, imprisonment and harassment of tribe members who have refused to facilitate the project.

The Fehmarnbelt Fixed Link tunnel is poised to be the longest immersed tunnel in the world and will stretch 11.1 miles (18km) between the German island of Fehmarn and the Danish island of Lolland. There is currently a 45-minute ferry service that covers the route, but the tunnel will slash travel times to seven minutes by train and 10 minutes by car. Developers also hope that the tunnel will reduce air travel between the two landmasses. Similar projects to the Fehmarnbelt tunnel, such as the UK-France Channel Tunnel, have been built using a boring machine, but this underwater underpass will be put together using pre-built sections of tunnel.

Not everyone is impressed by the project though, and the tunnel has been subject to 10 separate lawsuits from: environmental associations concerned about noise pollution and risk to the reefs that lie in the vicinity of the build; the city of Fehmarn itself; other travel companies that serve the route such as Scandlines and Rødby ferry line; as well as three other municipalities and a farmer. All these legal challenges have been dismissed however, and contrstruction is set to be complete in 2029. 

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