You feel like you're in a forest, but you're actually walking amidst the branches and trunks of a single giant tree.

A Tudor-style castle in Brazil holds one of the world's largest armory collections.

The remnants of an abandoned, 19th-century gold mill along Aruba's rugged northeastern coast.

Shipwrecks, ruins, and turtles are all that remain on this haunting Caribbean ghost island.

This tiny tropical village was sick of anonymity so the locals made this sign, which actually changed the name of the town.

Metal horses galloping through a London fountain provide a link to the city's past.

The last remaining example of the boatmen's perches that once dotted the south bank of the Thames.

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

A kaleidoscopic warehouse-maze of handmade neon signs.

Bangkok celebrated its shifting monarchy with a militaristic homage to democracy.

This bridge made famous in a novel and on-screen wasn't actually built over the river Kwai.

Six times a day a train runs right through the middle of this Thai street market, sending vendors scrambling.

One of Ayutthaya’s most iconic locations is a mysterious, hauntingly surreal miracle.

This narrow Ghent alleyway is an officially sanctioned street art tunnel.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

This grisly effigy displays an early Christian martyr who was skinned alive and beheaded.

A fake medieval village in the middle of Turin.

This bronze boar's snout has been rubbed to a golden sheen by visitors seeking good fortune.

The largest Art Nouveau complex in the world is a Barcelona hospital with a 600-year-long history.

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

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

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

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