"Congress may voluntarily remain in session throughout the summer, in order that our Congressmen may be protected from the intolerable discomforts and dangers of the ordinary outdoor weather!”

A secret greenspace hides atop a Capitol parking garage.

Although built to generate electricity for Marylanders, this dam has become an all-you-can-eat buffet for American bald eagles.

Come for the Italian food, stay for the taxidermy and giant statues.

The longest covered bridge in Delaware.

These ruins of an octagonal stone school that was later used as an A.U.M.P. church exemplify a popular school design from the 1830s.

Four bald cypress trees in Lafayette Square, across from the White House, mark the southern edge of a 100,000 year old cypress swamp.

The 72-foot giant escaped confinement in a large patch of mulch only to be reburied in the sandy shores of the Potomac River.

The penultimate and final resting places of British General Edward Braddock—minus a few bits and pieces.

This icon of the Atomic Age now lays dormant.

An Irish Memorial commemorating those who perished due to potato blight.

A field of nothing but boulders which resembles a giant's gravel driveway.

In the bowels of a 19th-century brewery lurks a fine-dining restaurant offering an array of themed feasts.

This hidden gem of a garden has one of the only surviving Victorian ferneries in America.

A toxic ghost town sitting atop a massive coal fire.

This beloved Baltimore spot features caged dolls, a giant Pez collection, and many, many mannequins.

The Pentagon sits on a former island that was in Virginia at low tide and D.C. at high tide.

The rogue roots are gradually consuming some of the historic marble grave markers.

The U.S. Fish Commission’s effort to mass produce carp.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

A line of blue paint marks the route of the inaugural parade.

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

A building shaped like the Army Corps of Engineers logo, because why not?

You could be standing at the site of one of D.C.'s most fatal tragedies and not even know it.