Oslo's historic toboggan run has been letting thrill seekers slide from train stop to train stop for over a century.

Tens of thousands of tiny bottles stuffed with various items.

An artist's mausoleum with a haunting echo.

One man's exploration of the human form, including the bizarre and delightful "Man Attacked by Babies."

This subterranean studio is filled with fascinating kinetic art.

This unusual elevator doesn’t stop or slow down.

This 1920s Amsterdam neighborhood was built as a giant experiment in concrete construction.

A public urinal so pretty, it was declared a national monument.

This basement museum explores the art and artistry of fascism.

This unattributed sculpture in Amsterdam is hiding in plain sight.

The attic of a four-century-old canal house hides a clandestine church.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.

This gorgeous reading room houses the oldest and largest art history library in the Netherlands.

The world's first zoo for microbes collecting the horrible and wonderful things living on and around us.

Museum preserving torture methods from the past.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

The world's only museum devoted to the wonders of fluorescence.

Once defending the city of New Orleans from invasion by sea, this fort faces an uncertain future.

A theme park that suffered massive flooding during Katrina was abandoned, and now proves irresistible to trespassing explorers.

A miniature rainforest is growing inside of a Midtown Manhattan office building.

A crumbling hospital from the 1850s on Roosevelt Island.