An ancient Roman theatre restored to its former glory in the Spanish city of Cartegena.

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

Stunning Roman aqueduct used for 1900 years and still standing.

This salt marsh in Southern France is as pink as the flamingos that inhabit it.

Bordered by forest on three sides and the ocean on the other, the Great Dune of Pilat is the highest sand dune in Europe.

A miniature city, once ruled by the Queen of the Netherlands.

Unsurprisingly, Holland is home to one of the most magnificent flower gardens in the world.

Invisible bridge parts the waters, invoking biblical images and preserving the ominous feel of an ancient moat.

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

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

Folklore and history carved into Brittany's coast.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

An ancient ossuary in Rouen.

This surreal statue brings a famous French novel about a supernatural cad to arresting life.

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

Paris' linguistic guide to the international language of, yes, love.

The celebrated eyesore created by starry-eyed sweethearts.

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

A 14th century bridge built as a fortress, where the devil lurks on one of its towers.

A park with one large cat sculpture and 15 smaller ones, all painted by different Colombian artists.

One of the largest underground systems runs under Canada's largest urban center.

This unique bridge physically lifts a piece of the road into the air to let boats pass by.

This Netherlands museum holds a gloriously mechanical collection of ornate musical automata.