A little marble compass above George Washington's (empty) tomb in the Capitol marks where D.C.'s four quadrants intersect.

Large, airy hallways hide within an impenetrable fortress that beckons urban explorers.

This gnarled old tree supposedly sprouted from seeds kept in the pocket of a 16th-century Spanish sailor.

One of the largest collections of socialist realist art shows the surprising depth of the official art of the Soviet Union.

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

Artwork tucked within the trees greets visitors with surreal sonic experiences.

The labyrinthine home of the National Archives of Estonia is an experimental blend of architecture, art, and history.

An impressive collection is dedicated to the legendary beast.

Russia's giant concrete QWERTY keyboard is likely the largest in the world.

The randomness of this wall of lava lamps helps encrypt up to 10 percent of the internet.

At the United Kingdom's only residential library you can sleep among the books.

A cave 150 feet beneath Kansas City is the perfect climate for growing 10,000 delicate orchids.

A visionary Italian architect created an impressive cluster of concrete structures for a family's private tomb.

Though technically an illegal structure, this eclectic DIY apartment complex is beloved by its residents.

A meow-velous tribute to a beloved street cat, made famous on the internet.

A Frankenstein blend of science and art allows one tree to produce 40 different types of stone fruit.

Find out what it sounds like when doves cry at Prince's recording studio estate turned museum.

Every winter, the wind carves blocks of frozen water into beautiful abstract shapes inside this unusually curved tunnel.

These ancient sunken lanes were naturally tunneled into the soft ground by countless footsteps.

Mirrored floors and arched shelves create the illusion of an infinite tunnel of books.

A Gothic-style abode built to accommodate the church's three resident peacocks.

This rusting remnant of the local herring industry is being given a second life.

The largest open-air contemporary art center in Latin America is a unique experience in the Atlantic Forest.

The world's largest grapevine has produced a delicious harvest at Hampton Court Palace for almost 250 years.