The largest bell in the world has been swinging high above a Cologne cathedral for almost a century.

One of downtown Berlin's last reminders of its Communist past.

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

The most visited, and possibly most controversial, museum in Germany.

A battle between nature and architecture in the Cambodian jungle.

Khmer Rouge's high security prison.

One of the biggest markets in Asia, under one of the continent's largest domes.

A fearsome dragon clings to a corner of Munich's city hall.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

The final resting place of the great navigator, or maybe his brother.

The world's largest wooden structure.

Week-long block party becomes a competition for the best decorated street.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

This medieval city gate is now a blend of the past and the modern world.

This shining multicolored metro station deep under Naples is said to be the most beautiful in Europe.

Skulls from the plague of 1656 and World War II bombings are united by a cult dedicated to caring for the ancient dead.

Formerly the world's largest, this Willy Wonka-esque contraption runs 24/7.

A colossal floating restaurant built to look like a ancient Chinese imperial palace.

A serene space tucked amid the skyscrapers of Hong Kong's bustling financial district.

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

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

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