An abandoned concrete jungle surrounded by a lush park.

Once a dining hall for boarding school students, this lodge was a popular haunt for nuclear physicists working on the Manhattan Project.

The oldest continuously occupied public building in the United States.

The winter home of thousands of beautiful snow geese and sandhill cranes.

The 7,000-year-old calcium carbonate formation creates a magnificent natural bridge.

Wedding chapel's mysterious spiral staircase said to be miraculously constructed.

A preserve with 75,000 ancient drawings remains the realm of public – not just scientific – exploration.

This quirky hot springs town known to locals as "T or C" was named after a radio show.

A unique geological area spiked with wind-carved rocks that resemble teepees.

The official atomic museum of the United States explores the explosive and productive history of a much maligned energy source.

A small metropolis of Pueblo cave dwellings have been carved right into the hillside of this national monument.

An immersive environment that is part haunted house, part choose-your-own-adventure, and part jungle gym.

A museum dedicated to the alleged Roswell Incident.

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

Thousands of pieces of art have been carved into the rock at the site of an ancient volcanic eruption.

"I did this all while you were watching TV."