Mortarless walls that stretch for miles are a lovely solution for creating grazing land in the harsh terrain of the Aran Islands.

This exceptionally well-preserved ancient marvel also houses a small museum dedicated to Jordanian folk tradition.

Gladiators battle and chariots race daily in the ruins of a once-great Roman city.

The most gigantic, swoony, intimidating trio of fingers in all of antiquity.

Ruins of a German Castle on top of a towering stone pillar.

Hidden deep in the Guatemalan jungle is a turquoise paradise of natural pools, caves, and waterfalls.

Central America's deepest lake is actually a volcanic caldera, surrounded by three volcanoes.

A musical instrument played by the sea.

An underground city of salt.

Italy's curious field of mud volcanoes is named for being both gross AND salty.

Copenhagen's celebrated theme park and gardens.

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

Museum on earth sciences featuring a recreation of a famous curiosity cabinet.

Opulence and fantasy collide in this royal chair which is supposedly made with unicorn horns.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

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

The comedy and tragedy of Oscar Wilde is preserved in a Dublin park, captured in a sculpture of colorful stone.

The wreckage of a tragic plane crash is on display at this museum devoted to a famous Italian conspiracy.

In the world's oldest university is a stunning 17th century anatomical theater carved from spruce.

Italian poet Dante Alighieri is entombed in this small mausoleum in Ravenna, and his hometown of Florence has never been too happy about it.

This zoological museum began as the first great curiosity cabinet.

This cluster of little wooden huts once ground local farmers’ wheat into flour during the days of the Austro-Hungarian Empire.

Two geological phenomena in one precarious locale: a towering stone window, and a deep blue void.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.