St. Augustine's record-setting narrow street was designed to protect against pirates.

A luxurious 1880s hotel with its fair share of Tiffany stained glass, Edison electricity, and of course, ghosts.

A journey begins with a single step, and for many, the road-trip of a lifetime started at this Chicago intersection.

One of the few standing Roman lighthouses and a labyrinth of tunnels are a couple of the secrets at this historic castle.

Before becoming a poet John Keats studied here to become a surgeon.

Bombed and burned, this monument represents the often controversial ties between Vietnam and Cambodia.

A secluded, little-known temple hidden amid the dense jungle.

Khmer Rouge's high security prison.

This ancient structure is widely thought to be the oldest intact pyramid in the world.

This 19th-century Turkish bath house survived the Blitz of London and is now an events venue.

Formerly known as Saville Theatre, this mid-20th-century entertainment hub includes an ornate frieze.

Collection dedicated to brands, packaging and advertising.

This Polish cave has housed a dragon, a brothel, and an enduring legend.

An underground city of salt.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

A mysterious emblem tucked in an small alleyway is actually the coat of arms of a heroic medieval family.

These rare statues are one of the few remaining material witnesses to Old Prussian culture.

A huge wooden clock that is so beautiful its creator was forcibly blinded.

The site of the first battle of World War II.

Modern art commemorates one of the first military actions of World War II.

This antique thermometer honors the creator of the first universal temperature scale.

These plaques found across Warsaw commemorate the sites where executions or battles took place during the German occupation.

Hundreds of notes give thanks to the patron saint of lost causes.

The giant statue and its model solar system honor the native Pole who declared that the Earth revolves around the Sun.