A retrofuturistic art installation in the Pittsburgh Airport.

Pittsburgh’s largest and most detailed model train display began as one WWI veteran’s hobby.

Color-coded signs direct drivers on a network of routes designed to avoid Pittsburgh traffic.

An 18th-century Catholic church converted into an eccentric temple of music and bacchanalia.

This shop filled with oddities and knick-knacks is named for a 19th-century charlatan.

This public park was the site of the largest civilian disaster of the Civil War.

Hundreds of protractors affixed to surfaces all over the city.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

This giant disembodied horse head seems to balance impossibly on its nose.

A model of a dinosaur that was named for Andrew Carnegie stands outside the museum that also bears his name.

An imposing pair of sphinxes stand guard outside this Egyptian Revival tomb.

This mesmerizing kinetic sculpture blossoms endlessly in the breeze.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

Stockholm's deepest subway station is also a stunning ecological wonder.

Stockholm's tiniest statue is of a small boy looking at the Moon.

Several cannonballs of mysterious origins decorate two buildings in Stortoget's main square.

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

A 130-year-old urinal is the oldest of Stockholm and perhaps all of Sweden.

This small museum nestled inside a souvenir shop is dedicated to Sweden's most well-known toy.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

Dine on food tied to Viking history and legend at this subterranean Stockholm spot.

Stockholm's narrowest alley is barely over two feet wide.

One of the world's first dedicated bank buildings in the world is now the oldest one.

A man has revenged his true love's betrayal through tears and stone genitalia.