Arrogance and quarreling are forbidden near these three sacred waterfalls.

A floating cat sanctuary on an Amsterdam canal.

This spaceship sculpture in the middle of the Slovakian capital looks like it just crash-landed.

A cheeky architectural easter egg.

Lyon's "Wall of the Silk Weavers" is one of the largest murals in Europe.

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

Millions of glowing microscopic organisms light up the waters of this luminous lagoon.

Swim or sail to this pie-slinging boat off the coast of St. Thomas.

This large stone off the coast of Martinique had a brief career in the Royal Navy.

The rusted remains of a victim of Hurricane Ike.

This staircase in a lush tropical grotto was built by enslaved laborers and renamed to honor Queen Victoria's role in ending slavery in the British Empire.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the first ‘Harry Potter’ film.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

Architectureal fantasy quarter of Rome.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

A 98-room castle in the middle of Toronto that bankrupted a 19th century electricity multimillionaire.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

Breathtaking and huge 430 year old maps of Italy.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

Liechtenstein's royal family calls this medieval alpine castle home.

An ancient Roman relief beautifully preserved on the façade of a house.

This statue of the great Argentinian car driver is located near a famous curve of the Monaco Grand Prix.