A physical reminder of Earth's ancient past, this rock results from the photosynthetic processes of some of the oldest forms of life.

This Native American cemetery features decades-old spirit house hidden behind pine trees and moss.

This 19th-century ghost town offers a stunning view of Lake Michigan and a journey through the region's industrial past.

This sprawling bookstore spans four floors and has more than a million books in stock.

The remains of an abandoned dinosaur theme park litter the woods just off the highway.

Abandoned concert venue legendary for its rock counterculture.

This Detroit ruin was once a gothic bastion of its community, but now it stands as a haunting ruin.

Hidden behind a wall for decades, this masonic lodge was only rediscovered during renovations.

This indie movie theater is one of only three surviving Mayan-themed theaters designed by “Detroit’s greatest theater architect.”

A once crucial portion of the Long Island railroad still lays abandoned, waiting to be turned into an urban park.

The home of aviation trailblazers, in a remote corner of the big city.

Read between the lines of the subway map to find the hidden abandoned Civil War fort.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

Hidden in plain sight on the Hudson River is an abandoned train station where nature has taken over.

This abandoned seaside fortress is now simply an imposing ruin being taken back by nature.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

Once America's longest-manned military fort, now an abandoned hulk.

The haunting, dilapidated remains of a former poorhouse on Staten Island's Greenbelt.

A legendary speakeasy bookstore returns from the brink.

Though its celestial ceiling is impressive, the true star is the vast collection of French books.

The iconic Manhattan corner that was once the site of the Beastie Boys' fake clothing store.

The oldest family-run luncheonette in New York, last renovated in 1948, still serves food and drinks the old-fashioned way.

Unique antiquarian shop specializing in globes, maps, and prints.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.