The exit of the largest prisoner-of-war escape attempt on American soil during World War II.

A totem pole of heads to represent the different stages of life.

This metro station doubles as an unintentional paleontology museum.

This handsomely carved wooden church is more than 800 years old.

These 400-year-old ruins are all that's left of the monastery where Ines de Castro was assassinated by the King of Portugal.

The oldest vestiges of Madrid found here, have been incorporated into this new museum.

This modernist bridge highlights the bear as a symbol of Madrid.

This little sun pays homage to a massive gate that once stood at this location.

A thorough look at the development and history of the underground's rolling stock of the Madrid subway system.

Where mountaineers were checked for lice before entering the city.

A grumpy old water goblin guarding an old mill on the Devil’s Stream in Prague.

This collection of 20th-century toys is filled with a lifelong personal toy collection brought from the U.S. to Amsterdam.

This is an amazing but little known tile mosaic mural that used to grace the lobby of an office building in 1958, but now can only be seen from the second floor of a Shoppers Drug Mart.

Hidden underground, a remarkable 10th-century bath complex survives virtually unaltered.

The longest continuous lava tube in the continental U.S. offers 2.5 miles of dark explorations for the adventurous.

This statue in Plaza San Francisco commemorates a beloved figure from 1950s Havana.

Legend has it that this stone moves down to the river sometimes to have a drink.

A tribute shrine where the Space Invasion street art movement started.

One of Antoni Gaudí's least-visited works, an homage to Catalan patrimony that mixes neo-Gothic with Modernista forms.

Mountain where Jesus was first tempted by the Devil.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

A tunnel that brings more than a century of history to life from the deepest parts of the Niagara Gorge.

Explore a remarkable 35-hectare sculpture garden located an hour outside of Lisbon.

A 30-foot neon sign that embraces community togetherness.