
Located in Chile, the “San Alfonso Del Mar Resort” boasts the world’s largest outdoor swimming pool, at 8 hectares. Click here for additional pictures.
It’s filled with about 250,000 cubic meters of salt water which, if you’re wondering, is roughly equivalent to about 6,000 standard backyard pools. It cost about $1.5 billion to build and maintenance alone is about $4 million a year[via OhGizmo!]