A towering spire in the fortress of Kalemegdan honors the victorious armies of Serbia during their struggles against the Ottoman Empire.

A futuristic, brutalist masterpiece that is also strangely prison-like.

A Red Cross memorial museum at the site of the Niš concentration camp that operated for four eventful years during World War II.

Nikola Tesla's ashes are held in a golden sphere, surrounded by his works.

A hidden church in a hidden courtyard tells the story of the Miracle of Amsterdam.

This old-school café is famous for serving coffee, chilaquiles, and the Cuban Revolution.

Gilded heaven for philatelists and architecture freaks, still in full working order despite sitting atop tremulous ground.

A grand entrance to one of the world's smallest Chinatowns.

An airy Art Deco space devoted to the weird and wonderful folk art traditions of Mexico.

Once the private home of China’s most legendary tycoon, getting inside this stunning mansion no longer requires an elite pedigree or acts of daring.

Site of the largest volcanic eruption in the last 25 million years, one which may have nearly wiped out humanity altogether.

The largest Chinese cemetery in the world outside of China dates back to the 15th century.

This fountain was once heralded as the largest in the world.

This Singaporean food-court stall was home to the world's cheapest Michelin-starred meal.

The ancient latrines of the Greeks, in all their public glory.

This community on a small Venetian island has taken to painting their houses in bright neon hues.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

The telescope that discovered Neptune.

The patron saint of spinsters grasps a container of dried blood.

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

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

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

This stucco building in North Africa was the first American-owned property on foreign soil.

Exploring the wilder, more passionate sibling of Erg Chebbi feels like discovering a secret sun-kissed planet from another galaxy.