One of Ireland's most infamous prisons for rebels including men, women and children.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

The picturesque birthplace of Icelandic democracy is drenched in the blood of its brutal past.

This stunning concert hall has become a symbol of Iceland's national recovery.

If a glacial river suddenly diving into a sheer chasm via a dramatic, multi-stage waterfall isn't peak Iceland, it's certainly close.

Medicinal spa created from the mineral-rich runoff of a geothermal power plant

A triumphant marble and bronze fountain depicting a 15th-century Hungarian king and his hunting party.

The first island in the world designated a light-pollution-free astronomical observation point.

The hallucinogenic center of the ancient world.

Beneath the impressive baroque cathedral that rises from the center of Berlin lies the largest collection of Prussian royals in the world.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

The most visited, and possibly most controversial, museum in Germany.

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

This church also serves as a lighthouse complete with a beacon.

These enormous, stern-faced statues greet visitors with lanterns, and sometimes costumes.

This irregularly shaped sea fortress has defended not one but three different sovereign states.

A subterranean house of worship carved right out of the bedrock.

The Guardian of Tallinn.

Iron Age "bog person" preserved for over 2,300 years.

Old Danish castle immortalized in Shakespeare's Hamlet.

Climb to the top of its spiral spire for spectacular views of Copenhagen.

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

Copenhagen's celebrated theme park and gardens.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”