One of the world's oldest and most massive living organisms is a grove of quaking aspens.

Ruins of a once-prized railroad station in New York.

A deteriorating 1990s Girl Scout camp in a beautiful lush park on Lake Ontario.

The factory for the popular Dumbo location, the Greenpoint shop is a quiet gem.

This natural rock "church" might not be a proper chapel but that doesn't mean it's not beautiful.

An abandoned 19th century quarry in the middle of the woods, remade by unnamed wanderers into a massive series of rock thrones.

With 3,000 bikes on display, the world's largest bicycle museum includes some famous rarities.

This dramatic rail curve was once the target of a failed Nazi attack.

The oldest surviving botanic garden in the United States.

North America’s largest collection of horological devices and home to a colossal clock with a dizzying array of features.

It would take 35 firetrucks to fill this enormous glacial pothole.

Pennsylvania's highest point is spotted with boulders which were pushed to the surface by nothing but cold.

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

A field of nothing but boulders which resembles a giant's gravel driveway.

Behold the rickety wooden glory of the world's oldest operating roller coaster.

This small museum dedicated to the painful memory of segregation is essentially a time capsule.

The only working large-scale tea plantation in the United States.

The secret city built by the Manhattan Project.

This replica of the Greek structure is in the heart of Nashville.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

Labor provided by Great Depression-era programs restored these 25,000 acres in Tennessee.

Mile-long cave system near Great Smoky Mountains.

Wild lights and sound effects turn a walk through some caves into an eye-popping 1960s tourist attraction.

Visit this playground of waterfalls, caves and sinkholes.