A wrecked ship dating back to the American Revolution was only recently discovered off the Delaware coast.

The remains of an old sawmill, gristmill and the surrounding industry dating back to the 18th century.

A completely round house designed for the Atomic Age.

This Great Depression-era creation was once known as the strangest house in the world.

Where America's first doomsday cult awaited the end of the world.

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

An abandoned cemetery lies in ruins as the surrounding forest swallows it whole.

Over 100 concrete munitions bunkers are all that remain of a Pennsylvanian village seized by the US government.

Sail through this subterranean show cave that is home to a legend that would go on to name nearly everything around it.

Frank Lloyd Wright's most iconic home dangles over a Pennsylvania waterfall.

Collection of trolley cars in the woods represent one man's attempt to preserve transportation history.

What looks like a simple quaint estate in rural Pennsylvania was in the 18th century home to a small monastic community.

A local prank turned town icon.

This titanic java kettle is one of the many kitschy landmarks located along America's OTHER famous highway.

Despite violent work crews and massive delays this abandoned canal tunnel was built to last into the modern day.

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

A labor of love built by local hang-gliding enthusiasts, this ideal launch spot was outlawed by the authorities and has since been largely abandoned.

Outsider art meets paleontology at this roadside reptile repository.

A pre-Industrial Age iron furnace and the site of a nearly-forgotten piece of Black history.

Built by the patriotic residents of Boonsboro in a single day.

A swimming hole in the historic industrial quarry that supplied the marble for the Baltimore Washington Monument.

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

There's a crumbling old mansion inside the Smithsonian National Zoo.

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