The loneliest island in New York.

Read between the lines of the subway map to find the hidden abandoned Civil War fort.

Eccentric concrete mansion and museum designed and built by hand from the inside out.

A historic arena where the Beatles played their first concert in the U.S.

Art deco landmark on the outskirts of Washington, D.C.

The national park was once a plantation estate.

The Byzantine, pre-Columbian, and medieval art at this stately mansion are some of the most under-appreciated collections in D.C.

This leafy estate is worth $18 million and is so grand it has two mailing addresses.

Fittingly, America's museum of architecture is itself a magnificently designed old building.

During the Industrial Revolution this “Temple of Invention” was full of intricate miniature machines and gadgets.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.

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

One of the dwarven trees dates back to 1625 and survived the Hiroshima bombing.

Home to items never before seen by the public.

Curtiss is a forgotten figure in the early history of flight.

A curious collection of oddities including a lock of Alexander Hamilton's hair and Harry Houdini's ouija board.

A desiccated merman and a walrus penis bone are among the oddities in this eclectic collection of shipwreck treasures.

Hundreds of glow-in-the-dark objects light up a museum in a historic zinc mine.

Fiji mermaids, mummified remains, and recreated cryptids are among the morbid oddities at this Maryland museum.

A parade of antique steeds offers a quirky ride through history.

Antique skeletons and taxidermy creatures were found crammed in a university closet.

A delightfully quirky blend of oddities spread throughout an old 1920s bank.

A surprising museum of 20th-century technology.