This stately building in Alexandria, Virginia was built by Freemasons to honor one of their most famous members.

An out-of-place Air Force radar dome is all that denotes this park as a former missile launch site.

An eight-sided home built during a brief octagon craze in the 1850s.

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

The resting place of a Civil War celebrity's amputated limb.

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

The ruins of this Thomas-Jefferson-designed mansion have been left to crumble since the Christmas Day they burnt down.

The skeletal white beams stand as a monument to religious dissent.

An alternate history park where the Union Army loses the war... to dinosaurs.

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

This museum devoted to the gothic author holds such interesting ephemera as his socks and walking stick.

Outsider art meets paleontology at this roadside reptile repository.

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

One day a year it is legal to jump off of this astoundingly tall bridge that spans an Appalachian gorge.

The "mysteries" of this quintessential roadside oddity were almost destroyed by neglect but were saved by fans of kitschy wonder.