A series of sculptures beneath the waves promote ocean conservation and support coral reefs.

This secret Australian garden was built on love after a man planted a random bulb he found in the ocean.

Built over an abandoned train yard, this hidden gem is full of winding paths and offers gorgeous views of Sydney Harbour.

This gracefully curving formation looks like a massive wave that was suddenly turned to stone.

An abandoned relic of the city's failed experiment with below ground transit.

An obsolete, vanishing traffic device warns Cincinnati drivers away from middle-of-the-road obstructions.

Where beautiful signs live on forever.

The private clubhouse for the members of the Academy of Magical Arts.

This 252 step staircase offers stunning views of San Jose.

The man who first patented the Ouija board rests in peace beneath a headstone that playfully reflects that achievement.

The only structure left with direct ties to the Salem witchcraft trials of 1692.

Commemorating the spot where the famous scientist fed his pigeons.

One artist's love letter to his city and its citizens plays out across dozens of bright murals painted on the sides of decrepit buildings.

A display of magnificent stained glass windows is the first exhibit of its kind.

A century-old hotspot for jazz, frequented by everyone from Charlie Chaplin to Al Capone.

This whimsical Oz-themed park had a wonderful impact on the surrounding neighborhood.

This unauthorized stone mermaid was secretly carved out of public stone before being permanently preserved.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

A Japanese cat island also populated by the descendants of a band of banished samurai.

Once a black market electronics marketplace, now an otaku shopper's paradise.

This elegant carving of the Buddha guards a small Buddhist temple within a cave.

A forsaken beachfront condo abandoned after the Boxing Day Tsunami.

Discovered after draining a local pond, these ancient man-made caves are still a complete mystery.

Sidle into a side alley for a taste of sumo wrestlers' traditional hot-pot soup, in a tiny restaurant founded by a former competitor.