10. Largest swimming pool in the world
There's a resort outside of Santiago in Chile called San Alfonso del Mar that is home to the Guinness World Record Holder for the biggest swimming pool in the world! It took five years and nearly 1 billion US dollars to build the pool, which opened in 2006. It's 1,000 yards long, covers an area of 20 acres (that's about the size of 16 football fields!) and reaches a maximum depth of 115 feet.
The massive structure is filled with more than 66 million gallons of seawater, and features views over the San Jeronimo beach. It took five years to build and apparently costs about 2 million dollars a year to maintain!