Every four years, a host city spends billions of dollars building competition venues to host the Summer Olympic Games.

Constructing facilities for the world's top athletes comes with a hefty price tag – and recouping the money once the events are over is nearly impossible. While many buildings have been repurposed, other Olympic arenas, pools, and stadiums built since the turn of the millennium have been completely abandoned. 

With the Paris Games in full swing, read on to discover how much money host cities have spent on the Summer Olympics since the year 2000, and see what remains of these structures today. We've also taken a peek into the future to see what's happening in the next host cities...

All dollar amounts in US dollars unless otherwise stated.