The Virginia farm where John Wilkes Booth met his grisly end is now largely forgotten.

An extensive, if one-sided, history of U.S. law enforcement's war on drugs.

This pre-Revolutionary War grist mill ground corn and flour for soldiers in seven American wars.

This unique historical monument features large concrete spheres designed to resemble fallen stars.

America's first public mental health facility.

The final resting place of two (or three) presidents, one vampire, and 18,000 Confederate soldiers.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

A sacred site for Native Americans surveyed by George Washington and owned by both King George III and Thomas Jefferson.

FDR's Art Deco hospital tower was hopelessly inefficient.

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

This massive swimming pool is the high tech home to the human-powered submarine races.

Home of the physician who set the leg of John Wilkes Booth after the Lincoln assassination.

The world's oldest continuously operating airport was founded by the Wright Brothers.

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

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

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

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

This English-inspired Maryland garden is home to acres of opulent plant life including bushes shaped into an entire fox hunt.

A blank headstone topped with a pile of pennies marks the final resting place of the infamous assassin.

The trials and tribulations of marking Poe's grave.

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

A museum dedicated to exhibiting remarkable outsider art.

There must be a pun in this haystack somewhere...

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.