A former major munitions plant that has been converted into a sprawling art space.

The semi-reclaimed ruins of this canal were once part of an ambitious plan to reroute the mighty potomac.

The bank that helped fund the Mexican-American War and the purchase of Alaska met its downfall after helping Augusto Pinochet launder money.

The little-known, 300-year history of the area includes former lives as a bustling tobacco port, parking lot, and industrial dump.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

The national park was once a plantation estate.

The oldest continuously operating fish market in the United States.

Decades before the scandal, this staircase on the river was a literal "water gate."

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

The site of the climactic scene from the classic horror film is now a historic landmark.

This rare triple-jurisdiction drawbridge passes through Virginia, Maryland, and Washington, D.C.

The bridge's highly-contested plaque (once again) honors Confederate President Jefferson Davis.

The whole world in one water tank.

The tallest The Church of Jesus Christ of Latter-day Saints temple in the world soars above the Beltway.

A star fort along the C&O Canal in western Maryland that protected America in three wars.

Built by the patriotic residents of Boonsboro in a single day.

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

This fort down the Potomac from Washington, D.C. was once the only defensive fort protecting the capital.

This scenic Maryland park was the site of one of the worst prison camps of the Civil War.

Once home to seven different roller coasters, Glen Echo has undergone many transformations since its founding in 1891.

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

The land is home to swimming ponies and a legendary 18th-century treasure.

Captain John Smith thought these cliffs were amazing in 1608 but sharks thought so 20 million years before him.

Near-constant high winds deform the trees on Spruce Knob, the highest point in West Virginia.