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."

A spring-fed pool so deep it's used for scuba diving as well as swimming.

A Prada store in the West Texas desert that is never open for business.

Mysterious glowing orbs float through the desert night.

Just below the surface, shrimp are producing temperatures hotter than the sun.

One-time winter retreats of prolific inventor Thomas Edison and his friend Henry Ford.

The "world's biggest dinosaur" once housed a creationist museum in its abdomen.

Located on 420 acres in the high desert, this spiritual center is dedicated to the "science of the future."

20,000 pieces in a Frank Gehry-designed building.

An ancient Egyptian temple in the middle of Madrid, Spain.

A giant granite cross remembers missionary Father Frederic Baraga, and his safe passage across an angry Lake Superior.

Duluth mineral magnates built this charming art deco lodge to be their private clubhouse.

Minnesota's highest point is a scenic vista marked by a plaque and armies of mosquitoes.

Half of a waterfall goes into the river while the other half seems to disappear.

The only road through the heart of Glacier National Park.

Fossils, railroads, and waterfalls!

Few other hotels can rival the grandeur of the Castle in the Rockies.

This incredible collection of vintage pinball machines can be played at 25 cents a pop.

This Arizona observatory is famous for investigations into Martian life, and as the place humans first spotted Pluto.

Home to the largest urban bat colony in North America, estimated at 1.5 million bats.

An enormous pink granite batholith, long attributed with spiritual powers by the Tonkawa Indians.

This rare vessel mixed luxury with labor before being converted to a museum and sometimes haunted maze.

The first hand-illuminated, hand-written bible since the invention of the printing press.