A mysteriously abandoned campsite in San Angelo State Park.

A curious cone-shaped structure made of wire and covered with antlers.

This sacred cavern, 400 feet deep, is home to millions of bats and an ancient burial ground.

On a dusty county road sit the ruins of a ghost town's abandoned church.

An entire subdivision was accidentally built on a flood plain, resulting in its eventual demolition—but the streets are still there.

A 131-year-old wunderkammer of Texas history.

A 2,500-pound wooden nickel makes this woodworking museum easy to spot from the road.

Over 100 million years ago, beach-bound dinosaurs left permanent marks on San Antonio's landscape.

Craggy concrete faces are hidden in the walls of this artificial cave along the San Antonio River.

A tall smoke stack and boarded-up buildings are all that's left of the pioneering plant.

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

Contrary to what one might expect, ice forms inside this small cavern during the summer and melts during the winter.

This lush forest valley was once mined for lumber to the extent that it was once nicknamed "The Pennsylvania Desert."

At this local mall, visitors are ushered through a 1940s jail exhibit.

This futuristic bridge is one of the longest self-anchored pedestrian bridges in the world.

An inconspicuous footbridge beloved by San Diego locals.

This San Diego museum, housed in a former Navy training facility, is dedicated to preserving women’s historic achievements.

Not truly a ship nor a building, the Navy's first and last "landship" is now abandoned due to clerical issues.

Behind this beachfront shop lies a spectacular, colorful sea cave with an equally colorful past.

Ruins of a once-opulent grand Victorian resort.

North America's largest accredited model railroad museum.

The freeway that never was.

This historic lighthouse was well known for the large number of women who served as its keeper.

These lush botanical gardens employ the most purrfect pest control force.