This golfball sized platinum iridium cylinder is the official starting point for all national weight calibrations

Easter in Westminster may be the only time and place to behold Edgar Allen Poe made entirely of Marshmallow Peeps.

Despite violent work crews and massive delays this abandoned canal tunnel was built to last into the modern day.

An intricately designed junk art house with four extravagant junk art cars hidden in the suburbs.

Crammed into a Baltimore row house is an oddities shop that sells everything from skulls to dead insects.

Remnants of a storybook amusement park hidden behind a strip mall.

Dating to 1793, this is the oldest building in Poolesville.

A total of 14 men held the title of "president" before George Washington—their historical legacies are enshrined in the lobby of a hotel.

She stares out across six lanes of traffic, clutching a musket and infant with determination.

Proto-CIA agents trained with grenades in the sand traps and fired machine guns from the fairways.

Politicians, bureaucrats, and military officers gathered in this field near the Capitol to settle their disputes with blood.

This ruined quarry once produced the distinctive red sandstone used for construction projects in Washington, D.C.

A lawn full of retired spacecraft on display at one of NASA's first research labs.

This 1830s store is believed to be the site of Harriet Tubman's first stand.

Two dozen pinball games hidden away inside a most unlikely location.

A model home in the Medical Examiner's Office in which grisly death scenes are staged to train forensic investigators.

An eerie, abandoned military base engulfed by nature and graffiti is now home to a local park.

An astounding collection of medical specimens, including bits of President Lincoln.

An eerie, decaying ghost town destined to fade into the forest.