A stunning 18th-century site where pilgrims ascend by a series of punishing stairs only to return via funicular.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

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

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

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

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

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

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

Once the grandest synagogue in medieval Spain, it now stands as a memorial of the 15th-century Jewish exile.

Among the oldest structures in Madrid, these Moorish walls once guarded the medieval city of Mayrit.

King Carlos IV laid the first stone during construction of this chapel.

When you're a great Russian Tsar, even your vomit gets a statue.

A little sculpture with a large wardrobe.

Rare wooden escalators lead deep down into an otherwise staggeringly monotonous tiled tunnel.

Europe's first floating restaurant is home to a hilarious legend.

While most bridges allow roads to pass over water, this one allows water to pass over a road.

The tallest waterfall in the Netherlands is a lovely, stepped feature that is only 50 feet tall.

Located inside Hoge Veluwe National Park, this museum began as the private collection of a prominent female art collector.

This disused VLF radio station is no longer in service but the surrounding town still bears its name.

Go inside a revolutionary, cage-less zoo where 70 species of monkeys roam free alongside their human visitors.