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

An art installation memorializing a tram stop, which became a tram stop.

The oldest skyscraper of Europe now stands dwarfed by the surrounding structures.

A large measuring stick marks the lowest point of a country that is partially under sea level.

Visitors can still take a train to this former train station turned museum.

The cutest way to stay safe in traffic.

At the base of this tower, a plaque marks the original center point of the Netherlands.

The Siege of Naarden ended in 1814, but the cannonballs embedded in the town church remain.

This monument pays homage to a classic Dutch tune.

A relic of Victorian grandeur hides beneath a busy South London road.

An ornate private entrance to the Vienna subway built specifically for the emperor.

The world's largest private telescope collection hides in a secret wing of a Dutch auto museum.

The world's oldest bookshop still in operation.

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

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

Get in line for Lisbon’s most famous sandwich.

One of the smallest bookstores on the planet.

The devil-defying mark left by a saint as a boy is visible inside Lisbon's cathedral.

In the Monastery of São Vicente resides a gallery devoted to a breathtaking collection of seashells.

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

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

This giant sculpture made of trash is a critique of society's wastefulness.

This historic streetcar system has been running since the 19th-century.

When this former hospital pharmacy closed in 2013 it already looked like a museum, so they turned it into one.