One of the most popular megalithic sites in Ireland stands as a humbler version of Stonehenge.

An earthwork sculpture built by Robert Smithson in the Great Salt Lake only reemerges during drought.

A working cattle ranch with remarkably well-preserved prehistoric petroglyphs and ancient ruins.

An absolutely beautiful 200-foot stained glass installation traces the evolution of knowledge.

The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

Australian Lake set aglow by Noctiluca Scintillans.

The graffitied ruins stand hidden within the Pennsylvania woods.

The tunnel's elegant proportions keep you snug with no claustrophobia freak-out.

A surreal landscape where fanged rocks rise from the ground and the ocean feels like a great mystery.

This abandoned boat sits on a nude beach, is shaped like a UFO, and is covered in graffiti.

Street artists transformed an abandoned air vent into the beloved Star Wars robot.

This whimsical stacked cabin looks like something out of a children's book.

Symbolic attempt to overcome the issues of life.

The quiet canyon has a tumultuous history involving a doomsday cult.

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

One of the best places to see feral Colonial Spanish Mustangs in the United States.

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

The Denver airport is guarded by a 32-foot-tall sculpture of a demonic horse.

A marvel of Byzantine engineering under the streets of Istanbul.

At high tide this strange footbridge appears to have no purpose whatsoever.

This palatial botanical garden is home to one of the largest pipe organs ever installed in a private residence, and a piece of Wood's cycad.

This once-popular otherworldly landscape was formed by one of the largest volcanic eruptions in history.

Come for the speed, leave in love with the desert.

The drama of nature in full effect in this Nevada State Park.