A striking symbol of the Bulgarian capital.

The preamble to the U.S. Constitution written entirely from vanity license plates hangs in the Smithsonian museum.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

These quintessentially English stepping stones were built for Victorian tourists.

A headstone notes where the most famous of Robin Hood's legendary Merry Men is reportedly buried.

This petite cutlery factory sits on the foundations of a defunct gasworks.

Eyam took steps to quarantine themselves and keep the plague from spreading.

One of the U.K's earliest public water supplies is within the "plague village."

Visit a surreal landscape so otherworldly NASA actually used it to train the Apollo 17 crew.

Partially collapsed lava tube and cave system complete with concert hall, underground pond, and unique albino crabs.

A seaside town with no sea in sight.

"Respectful to the dead, safe and sanitary to the living, dedicated to the Genius of Memory..."

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

Famously misunderstood wonder of the ancient world

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

The sign at the garden gate reads: "These Plants Can Kill."

Try not to get slimed in Tribeca.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

Louise Bourgeois' 30-foot-tall steel spider sculpture.

This amazing example of Valencian Art Nouveau looks more like a cathedral than a public market.

This colorful statue welcomes visitors to a Barcelona park.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.