A crumbling hospital from the 1850s on Roosevelt Island.

Tucked in the back of this amazing antique store is an important piece of medical history.

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

Once an opulent Art Nouveau hotspot, the Constanța Casino is one of Romania's most beautiful abandoned buildings.

A historic neighborhood church is reborn as a psychedelic arts collective.

The United States Capitol's former columns still stand.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

Home to items never before seen by the public.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

This grand gothic brewery has been pumping out suds for over a hundred years.

A bizarre roadside attraction and the first instance of miniature golf in the world.

Military and first responders can test their skills in a Foggy Bottom mock station down in Georgia.

Where school buses go to die and be reborn as whimsical works of art.

An eccentric inventor's castle home with its own indoor weather system.

Museum dedicated to awful artwork.

A steampunk wonderland that preserves America's history of industrial innovation.

Run by a eugenics advocate, this aging institution conducted secret radiation experiments sponsored by Quaker Oats.

A beautiful Victorian-era cemetery, complete with a miniature village.

Beautiful steampunk ghosts of early Massachusetts.

One of America's most historic homes also holds a startling literary legacy.

Three prestigious academic collections come together to create a world-class natural history museum.

An enormous, inside-out glass globe built in 1935.

19th-century operating theatre in which the use of ether was first demonstrated - plus, a skeleton and a mummy!