360° views of the city plus five floors of optical illusions and hands-on science.

Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

Famously misunderstood wonder of the ancient world

It houses the remains of a 17th-century version of the Titanic.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

Giant topiary dog once played a role in a terrorist bomb plot.

A living art gallery painted on a canvas of Monterey pine trees.

A darkly erotic open-air statuary in Catalonia.

Giant eggs, walls of bread, and nightmare surreality mark the largest collection of works by Salvador Dalí.

A gravity-defying "devil's bridge" that has a surprising architectural feature for its stability.

Wonderland replication in progress by one persistent man.

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

Gaze upon chocolate sculptures depicting everything from chariot races to Gaudí's famous church at this shrine to sweets.

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

A whimsical bridge adorned with decorative dragons.

This Slovakian statue of an emerging sewer worker might just be a bronze peeping tom.

This Slovak bridge is known both for its connection to a national uprising and its UFO-shaped eatery.

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

A misnamed well, with a deep dark past.

A pair of connected skyscrapers form this symbolic gateway.

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

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.