This Civil War monument was designed by an eccentric architect and Gettysburg veteran.

The second-largest giant sequoia in the world.

Beneath the southern end of the Golden Gate Bridge is the “Gibraltar of the West Coast,” a fort built to protect the San Francisco Bay from naval attack.

A 1930s Art Deco swimming pool with a design inspired by grand ocean liners.

This unique museum focuses on the Siege of Sarajevo through children's eyes.

This historic timepiece is thought to be the only public clock in the world that keeps lunar time.

This mysterious tower is said to enshrine a dormant seven-headed serpent that once protected Vientiane from destruction.

Perhaps the only one of its kind, the nearly-forgotten site once held mortal (and rigged) gladiatorial games between tigers and imperial war elephants.

The final resting place of 121 victims of the RMS Titanic, 42 of which may never be identified.

A simple memorial between a ball field and a skate park honors 21 men lost in a horrific mining accident.

Alongside a scenic road are the remains of crumbling World War II gun emplacement.

Housed inside a replica church, its collection honors the Black community displaced by the Halifax government.

A World War II gun battery sits at the easternmost point of North America.

The tiny airport in remote Newfoundland that inspired a hit musical is also a modernist architectural gem.

This oddly named town refuses to change its phallic moniker.

The first transatlantic wireless signal was received at this 17th-century fort.

Where a young athlete began his run across Canada after losing his right leg to cancer.

This historic lighthouse has been reincarnated as the perfect picnic place.

Swedish skyscraper with a 90° twist.

This chimerical bridge/tunnel appears to dead end right into the sea.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

Copenhagen's celebrated theme park and gardens.

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

This replica of the Greek structure is in the heart of Nashville.