Early habitat dioramas and home of the elusive gaff, the skvader.

A heated statue pays tribute to one of Sweden's great actresses.

Hidden in plain sight, Sweden's official ordnance datum is now abandoned.

This gem from the industrial age helps visitors and residents alike traverse hilly Stockholm.

When this 18th-century observatory's meridian was moved, it set Sweden's time back by 0.04 seconds.

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

"Only the dead get off at Kymlinge."

This grisly exhibit houses skeletons and weapons from a devastating 14th-century clash.

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.

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

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

A rare surviving Victorian greenhouse designed specifically to house giant water lilies.

Sweden's "good old days" painstakingly re-created in a model village.

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

Sweden's first nuclear reactor, R1, can be visited 25 meters underground.

A hidden bathhouse in one of Stockholm's oldest and busiest neighborhoods is open to anyone who can find it.

The biggest museum dedicated to insects in North America, one of the largest in the world.

This charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

A rare view of a preserved Victorian science museum.

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

A haunting statue called "Eternal Silence" has quite the reputation among visitors with active imaginations.

An antiquated German apothecary on Chicago's North Side.

100 years later, they're still down there.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.