New Hampshire's first neighborhood is now preserved as a historic village with live action role players.

Once the future of underwater combat, this old sub is now open for visitors to muck around in.

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

This beloved marketplace mascot poops money and grants good luck.

This elaborate towering structure was once famed for its revolutionary height.

This charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

Yo, Adrian!

The remains of a community that was forced to move for a dam that never materialized still rot in this Pennsylvania park.

The internal railway of one of the biggest steel plants in America has been transformed into a linear park with unique industrial views.

A diorama of the Civil War, fought by cats.

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

The train collection of an eccentric New England seafood mogul is now a National Historical Site.

A museum dedicated to the history of electric interurban transit near the home of the first electric trolley system in the United States.

Board a mine car and descend the #190 slope 300 feet underground into the Clark Vein of coal.

Tour the dark and beloved poet's former cobwebbed basement, which may have inspired "The Black Cat."

The world’s first penitentiary, meant to be humane, drove men insane.

Free public park and gardens filled with peacocks and peahens.

Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

This unique structure in suburban Austin is made up entirely of other people's castaways, and constantly changing.

World War II-era bunkers are hidden under the beaches of this picturesque park, which is still scattered with wartime watchtowers.

World War II bunker still standing on the New Jersey beach.

Rusting away on the edge of New Jersey are the remains of a Cold War missile launch site.

Now abandoned, the first public health hospital in the U.S. saw more than one million immigrants from around the world.

These unassuming lighthouses have seen the first reading of the Pledge of Allegiance, the first wireless transmission, and more than one mystery.