Once the home of a hermetic monk, this cave now houses a small church.

A whimsical sculpture garden right out of a children's storybook.

Danish tourist destination well known for open stalls where vendors sell marijuana on the street.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

A 19th-century subterranean reservoir repurposed as a contemporary art cave.

This deconsecrated church has seen many uses, from a tobacco storehouse to a cinema.

The only museum with its curator—and her pets—buried inside.

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

Where Venice's gondolas go for a tune-up.

The marble facade hides a little-known medical museum with early surgical instruments and rare copies of canonical texts.

Thousand-year-old Viking runes adorn an ancient Greek lion at the entrance to the Venetian Arsenal.

One of Jeff Koons’s largest sculptures and his first commemorative work.

This striking fort on the Maginot Line looks just as it did after being destroyed in the Fall of France.

There has been an astronomical clock on this spot since the 14th century.

The curious underground history of keeping Paris clean.

This ruined castle perched atop a rocky peak is a great place for a hike.

The oldest hydroelectric plant in Czechia is now a museum.

Tall columns of volcanic basalt make up this improbable-seeming rock formation.

Once a path for Jewish funeral processions, this unassuming alleyway is rich in local lore.

A collection of artworks exclusively created by the mentally ill that was almost burned by Nazi culture police.

This former steel and coal plant is now a neon-lit industrial fantasia.

Explore the complex ecology of this multifaceted nature preserve by riverboat.