This ancient theater was once the home of fierce gladiatorial battles.

Thousands of flamingos and other bird species flourish in these Camargue wetlands.

The mental institution where Van Gogh created some of his most famous work now allows guests to walk in the artist's footsteps.

This fascinating abbey is considered the oldest monastery in the region.

This ancient Roman bridge and aqueduct still stands as a wonder of classical construction.

For over 300 years this little carving has been the city’s good luck charm.

An image of the legendary saint stands in the shadow of a cathedral she liberated.

Europe's "only museum dedicated to the decapod" is full of quirky and absurdist displays, including one featuring the "famous" Giant Crab of Margate.

A hands-off space for graffiti artists to hone and display their skills.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

Nicolas Schöffer's massive interactive sculpture was assembled in 1961 and brought back online in 2016.

This giant urban staircase was built to keep the city's brave fighting men from getting waylaid in the red light district.

A marble Lucifer hides behind the pulpit of this Gothic cathedral.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

The largest underground lake in Europe.

Welsh literary history is preserved in the delicate pages of these medieval manuscripts.

Originally meant to hold a statue of King William IV, this support sat empty for years. Today, it hosts a rotating cast of public artwork.

An aptly-named street near the birthplace of the modern LGBT rights movement.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

A granite plane marks the site where a French aviator completed the first airplane flight across the English channel.

The somber sculptures commemorating Irish Famine on the river Liffey in Dublin.

A public work of art that also provides some relief from the summer heat.

Strange rumors surround the artist who created these solemn metal guard dogs.

Martin Bricelj Baraga's monolithic sculpture measures the blueness of the sky, and changes color to match it.