The ancient mosaics here are considered among the finest in the world, and serve as a stunning record of Greco-Roman daily life.

An ancient burial ground believed to have been used for ritual sacrifice.

Two stone columns flank the grand Venice square, but there were supposed to be three.

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

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.

Macabre astrological automaton clock dating to the late 1400s.

A haunting statue called "Eternal Silence" has quite the reputation among visitors with active imaginations.

It's good luck to be mocked by this monkey.

One of the most well-known city festivals in the world.

This private museum is packed with 20th-century traffic and technology artifacts.

The unusual sculptures are believed to be powerful political symbols.

A Serbian church lit by chandeliers made of weapons.

A statue in Budapest's Liberty Square honors the former U.S. president's efforts to end the Cold War.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

The statue of John Harvard isn't actually John Harvard—or even, technically, the founder of the school.

Impossibly life-like natural history models created out of glass by a father and son.

Three prestigious academic collections come together to create a world-class natural history museum.

Millions of numbers carved in glass represent the tattoos forced upon victims.

A former waterfront market is now in the center of town due to some interesting Boston engineering.

The massive machine creates cracking displays of indoor lightning.

Mrs. Mallard and her brood are a beloved fixture in Boston Public Garden.

Berthed at the Charlestown Navy Yard in Boston, "Old Ironsides" is the oldest commissioned warship still afloat.