All that remains of the once-booming chain is a single orange-roofed restaurant.

Senators used to relax in the nearly forgotten marble tubs now hidden in the U.S. Capitol Building's basement.

Read between the lines of the subway map to find the hidden abandoned Civil War fort.

The sole remaining outpost of a once-thriving South Carolina chain still sells “pic-a-nic” baskets.

This grounded passenger jet is now a restaurant, complete with rows of seats and “flight attendant” servers.

A rare cluster of alien-like plants grows along a dusty highway.

This Seattle joint serves food inside an old train car once used by FDR.

Great Britain's only hat-making museum.

This historic funicular system combines the old with the new while offering delightful views over the surrounding valley.

An enormous, inside-out glass globe built in 1935.

Four giant movable street lights decorate this modern Rotterdam square.

A King Kong-like gorilla hangs from the top of this commercial building in Tokyo.

An actual 1957 Cadillac De Ville, encased in 15 cubic yards of concrete.

Where the sleeping monsters of Scotland's oil industry are left to rust.

This abandoned oil depot produces world's longest echo in a manmade structure.

The southernmost outpost of the Russian Empire in colonial America.

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

A hidden three-foot-wide house separates these two regal churches.

A time capsule of Floridian history fights to survive on the banks of Chokoloskee Bay.

A subterranean world of tunnels links several buildings of this rare 19th-century asylum.

The illuminating collection of L.A. street lights is run by the city and only opens one day per month.

An Irish church where an 800-year-old mummy is reaching out of his coffin as if to shake hands.

Natural rock water slides hidden in the remote forests of northern Idaho.

Megachurch turned Catholic church comprised of 10,000 glass panes.