Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

Fresh wooden posts have been added to ancient holes to recreate a primitive henge clock.

Mai Tais and Navy Grog served up in one of the original tiki bars.

Beside some power panels, a plaque celebrates the history of an alternate world.

A unique work of art that was created without permission.

Cryptid lake monster honored with its own monument.

A surreal, interdimensional shopping center and portal to another universe by Meow Wolf.

San Francisco's newly reopened hands-on science museum.

A collection of noses tucked inside an art museum reveals how times have changed.

A novel collection of medical curiosities housed in an 18th-century surgeon training academy.

The art museum is decorated with creatively remodeled pre-Nazi swastikas.

This pair of gilded girls atop an Art Deco building in Copenhagen were built to function as a weather indicator.

Long before ultrasounds and modern testing, medical specimens like these conjoined twins helped physicians learn about congenital anomalies.

Site of the first radio and telephone broadcasting companies in Copenhagen.

One of Scandinavia's largest mosaics pays tribute to Danish art and science luminaries.

Positioned outside a church, this sinister folkloric figure incited protests in both 1902 and 2002.

Once a meeting point for great thinkers, and the midpoint of the country.

This bridge's unique architecture honors nautical heritage and encourages self-awareness.

Visitors are treated to a stained glass kaleidoscope interior inside this work of art.

Bored potato-guarding Nazis etched their thoughts onto a brick storage building in Copenhagen's Meatpacking District.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

Opulence and fantasy collide in this royal chair which is supposedly made with unicorn horns.

Climb to the top of its spiral spire for spectacular views of Copenhagen.

Danish tourist destination well known for open stalls where vendors sell marijuana on the street.