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

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

Every drop of D.C. tap water flows through this old waterworks.

A secretive collection featuring objects that were designed specifically for U.S. intelligence operations.

The ruins of this long-abandoned unsuccessful gold mine can still be found.

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

North Carolina's finest examples of Native American pictographs have survived for 5,000 years.

Railroad came. People came. Railroad left. Town died.

A 300-yard long natural tunnel runs through a ridge deep in the Appalachian Mountains.

This pun was simply waiting to come to life, and one defense contractor made it so.

This Virginia railway overpass is said to be haunted by a serial killer in a rabbit costume.

One street divides a single town that stands in two U.S. states.

The highest point in Virginia can only be reached by passing through ponies and flowers.

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

A railroad tunnel that, upon its completion, was considered one of the engineering marvels of the modern world.

The highest point in Maryland is only accessible by hiking through another state.

The brainchild of Eleanor Roosevelt, her "Little Village" was a collectivist dream.

America's post-nuclear-attack chambers of Congress.

This abandoned dream castle and its cemetery look out over the city that once inspired their creation.

There are more than 4 million bricks inside this unofficial Lego museum in a former middle school.

Beyond the usual stories that attend old prisons, this one has deep bloody undercurrents.

Bubbling up from deep underground is the warm crystal clear water that fills the Warm Springs Pools, America's oldest spa.

Hikers can still stroll beneath the long conveyer of this abandoned mining facility hidden in a West Virginia river gorge.