Surrounded by traditional homes, this Tolkien-esque dwelling stands out on a quiet street in suburban Maryland.

The twin towers in this Chicago fountain use 50 foot tall video screens to spit on people.

These trees are living witnesses to events that inspired poet Walt Whitman’s service during the American Civil War.

The hidden offices underneath Memorial Bridge have been locked up since 1976.

There's a crumbling old mansion inside the Smithsonian National Zoo.

The oldest surviving one-room schoolhouse in Montgomery County, Maryland.

These figures float and flutter in this fountain crafted by famed Swedish sculptor Carl Milles.

The largest cemetery for enslaved people in Loudoun County was almost lost to history, if not for the research of a minister.

This church is known as "The Home Church of George Washington and George Mason."

One of the only memorials dedicated to journalists who died in combat.

This Maryland farm is known for its amazing corn mazes and its 30-foot junkbots.

A pre-Industrial Age iron furnace and the site of a nearly-forgotten piece of Black history.

Need a hardcopy of the 50-title Code of Federal Regulations? This is the place.

Housing the National Women's Party since 1929, this historic house is now a monument to the fight for gender equality.

Before founding the American Red Cross, Clara Barton had a tremendous humanitarian impact by locating thousands of missing soldiers.

This unassuming passageway played a key role in one of the most important events in U.S. history.

D.C.'s first central library was born out of a chance encounter with the philanthropist whose name it bears.

The house where John Wilkes Booth conspired with his co-conspirators.

Hidden within an idyllic suburban garden is a memorial dedicated to the victims of a terrifying spree of killings committed on U.S. soil.

A historic cemetery filled with quirky faux wood art and unique tombstones.

A state park that once served as an important river crossing, and now offers protected lands for endangered plants and animals.

Featuring the the longest lift span of any vertical-lift bridge in the world.

A hidden passageway now marks the site of an assassination attempt on Ronald Reagan that some say broke a 140-year-old curse.

Cold War intelligence agents monitored communist embassies from an attic in a former pigeon coop.