Spinning silently in the lobby of an Art Deco masterwork is a massive vintage model of the Earth.

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

Mysterious 500-year-old tapestries depict a unicorn hunt.

A tiny museum housed in a New York freight elevator specializes in the "overlooked, dismissed, or ignored."

A clock set into the concrete outside a Manhattan jeweler has been telling time underfoot for over a century.

A starship has landed in Texas, a welcome break for weary travelers from a drab stretch of I-35.

Cockroach Museum features roach celebrities and live hissing cockroaches.

This crumbling UFO is one of only a few remaining "moveable ski chalets" of its kind.

It specializes in outsider art and artifacts of secret societies.

Elevated freight railway turned wildly successful urban park.

New York City's smallest piece of private property.

Hidden in plain sight on a pair of Manhattan subway tunnels are a pair of public instruments that sing to each other.

A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

A whimsical, but often overlooked clock in Park Avenue.

The world's oldest hologram gallery and the labyrinthine laser laboratory of a holography pioneer.

Cryptic messages embedded in the New York City sidewalk.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

Be it nature, art, or abandoned military architecture this eclectic German "museum" has you covered.

The fairy tale castle of the "fairy-tale king."

An industrial relic is now one of Europe's most staggering art spaces.

Unchanged for centuries, this medieval library keeps its books in chains.

This Netherlands museum holds a gloriously mechanical collection of ornate musical automata.

Peek through a transparent pyramid and drink in the mountain made of books.

Ruins of a once-opulent grand Victorian resort.