A open air theatre built on a cliff by an eccentric British woman.

Travel through the hidden underbelly of the city in colorful tunnels filled with art and history exhibits.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

Experience what life was like in Ireland during the Viking and medieval ages.

Amidst the bustling streets of Dublin, there is a hushed garden that is dedicated to "All those who gave their lives in the cause of Irish Freedom."

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

Nordic giants resurrected from the sea and restored to their former greatness.

An enormous playhouse designed to look like 21 stacked Lego bricks, with another 25 million colorful Legos inside.

Old Danish castle immortalized in Shakespeare's Hamlet.

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 unusually circular centenarian barn became a Route 66 icon.

This museum holds not just a world class collection of firefighting artifacts and gear but even the region's first fire station itself.

A larger-than-life monument to the overlooked women who braved Western expansion and broke down societal barriers.

The fifth tallest statue in the United States is a shirtless monument to the oil worker.

The collection is housed in an exquisite mansion that makes you feel like you've been transported to an Italian villa.

This ostentatious Italianate palace of an Oklahoma billionaire is filled with several themed mini-museums.

One believer transformed a local curiosity into proof of Vikings on the Great Plains.

Collection of skeletal systems from the "world's leading supplier of osteological specimens."

The future of roadside attractions is this sci-fi soda mecca that is home to a 66-foot tall neon pop bottle.

The last fully functional fortress of Germany's World War II Atlantikwall.

Norway's oldest cathedral still in use.

The design of this beautifully crafted building was inspired by Norwegian glaciers.

For six months of the year, three giant mirrors direct a pool of sunshine onto this otherwise occluded town.