This cavern was used as a hidden hospital and safe house during the Vietnam War.

Twice a day a speeding train passes only inches from the homes of this residential neighborhood.

The knock-off oil painting capital of the world.

130 replicas of world wonders squeezed into just 118 acres of space.

The world's longest outdoor covered escalator system transports commuters through Hong Kong's hilly terrain.

Teeming with illegal goods and services, this towering maze of vice is also a popular tourist accommodation.

Remnants of the most densely packed city in world history, that thrived on anarchy for 30 years.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

Climb to the top of the world's largest seated bronze Buddha.

These azure waters were thought to lead to the Mayan Underworld.

An ancient system of freshwater caves filled with animal bones, including that of species long-extinct.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

The Columbia Road Flower Market is now open every Sunday, rain or shine.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.