The abandoned grounds and derelict greenhouses of this once-magnificent Edwardian estate are now a nature preserve open for exploration.

This futuristic airport terminal was abandoned for decades before reopening as a hotel—with a vintage plane of its own parked out back.

The oldest living organism in New York City. Maybe.

A long abandoned hospital building on the outskirts of NYC.

An abandoned Gold Coast-era mansion once intended for the exiled ruler of Albania, who never arrived.

All that remains of a magnate's dream home is a historic gate and an abandoned public pool.

One of the world's most definitive collections of musical instruments, spanning all cultures and historical periods.

A six-ton, 12-foot-tall concrete prairie dog is touted as the largest in the world.

The highest point in South Dakota contains the ashes of Valentine McGillycuudy, the "Holy White Man."

One of America’s oldest and spookiest hotels, thanks to the residency of ghosts, dead presidents, and Alfred Hitchcock.

A four story, football field-sized, nine-grotto creation made of shells, minerals, and rare stones.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

This prehistoric sinkhole lured exclusively male mammoths to their death, much to the delight of science.

A giant pair of thick black glasses mark the tragic demise of a trio of rock and roll legends.

A roadside collection of over-sized iron creations that are a bit more macabre than most.