This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

Wooden cutouts of the fictional family from the popular Swedish comic strip take a stroll along the side of the road.

This homeless brass fox tugs at your heartstrings from the foot of a Stockholm bridge.

This Stockholm light tower can be controlled by anyone with a smartphone.

The remains of Alfred Nobel's first nitroglycerine factory can still be found on the shores of a Swedish bay.

This chimerical bridge/tunnel appears to dead end right into the sea.

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

The world's oldest bookshop still in operation.

Located in the thermoelectric factory that once powered the entire city, this Portuguese museum is shockingly fascinating.

Building owners can take out tiles for free at this repository for historic building materials.

A plaque hidden in the law faculty at Leiden University honors the first scientist to make liquid helium.

A giant yellow phallus sculpture hidden in the gardens of the Museum Boijmans Van Beuningen.

A nuclear reactor created for Eisenhower's "Atoms for Peace" campaign is now used for research at a Dutch university.

The world's largest bicycle shelter can hold more than 12,500 two-wheelers.

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

Inside this metro station is a section of the city's former medieval fortification.

The location of the world's first telescope demonstration.

This giant radio telescope would be a rusting ruin if it hadn't become such a beloved relic.

This 11th-century castle sits so low you can't see it behind the surrounding buildings.

This hotel was once home to a steamliner company and became the final rest stop for Europeans heading to the New World.

Four giant movable street lights decorate this modern Rotterdam square.

The Netherlands' first car tunnel has an unusually rectangular shape.

This gigantic monument hidden in the woods was built to thank the Dutch for sheltering Belgian refugees during World War I.

A modern reimagining of a medieval city gate.