This building has a giant piercing through one of its corners.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

This domed temple was built in a hidden cave mouth as a refuge for sinners seeking absolution.

A gorgeous medieval library where the books are kept in chains.

Filled with goldfish swimming in a shallow pool of sea water, this ancient crypt is more wishing well than burial site.

The remains of an ancient Roman city are hidden underneath Bologna's beautiful public library.

This 6th-century church has the largest and best-preserved collection of Byzantine mosaics outside Constantinople.

This natural gas vent certainly earns its name as the smallest volcano in Italy.

An art museum inside an active factory.

A small island dotted with old, historic Finnish buildings.

No matter how many times this community-run sauna gets destroyed, it always rises from the ashes.

When Azorean green tea meets volcanic hot springs water, a luminous brew is born.

A monument in the Belarusian city of Polotsk claims to mark the exact midpoint of the European continent.

César Baldaccini's iconic sculpture of a 40-foot thumb stands tall in La Défense.

A tribute to a Ukrainian heroine who went undercover and killed several Nazi operatives.

A quirky collection flush with information on commode culture from ancient times to modern day.

The medieval prince founded the first library in Ukraine at Saint Sophia's Cathedral where he was interred.

The bridges portrayed on EU currency aren't fictional anymore.

This legendary dessert was served to Nobel laureates for decades.

On a small Slovenian island, diners can mix and match a classic cake into dozens of sweet and savory flavor combinations.

Ancient ruins hidden underneath a modern luxury hotel.

Stockholm's deepest subway station is also a stunning ecological wonder.

The labyrinthine home of the National Archives of Estonia is an experimental blend of architecture, art, and history.

This salad has two key ingredients: hearts of palm and green ice cream.