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

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

The best place in the world to buy tinned fish.

A hidden three-foot-wide house separates these two regal churches.

Elaborate tile work in this railway station tells the story of Portugal.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

The stunning interior of this Gothic church is covered in ornate gold details.

A unique seaside cave where Aleister Crowley faked his own death.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

This neon blue river gets its color from a unique mix of bacteria and volcano minerals.

Limestone caves with spectacular showcase chambers.

Cabaret where the show girls are all androids, and the patrons couldn't be more pleased.

A rare water-powered funicular, it uses a huge tank of water and gravity to do its work.

Museum dedicated to the terror regimes of Hungary.

The hidden jewel of Disneyland: a members only playground for the Disney elite.

An elaborate shrine dedicated to the four corners of the world unfortunately misses its mark.

Race through the maze, get your name on the sign.

A massive underwater sinkhole made famous by Jacques Cousteau.