Hundreds of drawings left by the land's previous inhabitants remain mysterious.

Dig for your own trilobites in this goldmine of invertebrates.

One of the American Southwest's most extensive collections of Navajo rock art.

In the remote high desert of New Mexico, a strange array of poles beckon fury from above.

Twice a year, visitors can tour the desolate site that birthed the Atomic Age.

The farthest you can be in the contiguous U.S. from a McDonald's location.

The largest man-made crater in the U.S. marks the spot where we once tested mining with nukes.

A picture-perfect town, perfect for blowing up.

US-50 in Nevada is known as "the Loneliest Road in America," but this earlier iteration of the route is even lonelier.

Pennsylvanian mass grave and possibly mass murder.

This splendid Versailles-inspired mansion has the largest French-style formal gardens in North America.

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 might just be the TARDIS of bookstores.

A rare view of a preserved Victorian science museum.

In the early 1800s, surgery was also a show.

This little-known collection holds everything from "Dracula" notes, to the manuscript of "Ulysses," to the forged works of Shakespeare.

The sounds of the world's largest fully functioning pipe organ dazzle shoppers at a Philadelphia Macy's.

Huge masonic hall in Philadelphia with lavishly themed rooms.

Hidden deep within New Jersey Pine Barrens is a massive graffiti wonderland.

In the woods of New Jersey lie the ruins of a munitions village abandoned after World War I and the remnants of a 1920s wooden racetrack.

This historic iron-working village is now a ghost town so immaculate that it looks as though it was recently built.

The museum calls itself the "National Museum of the Paranormal" and is full of eerie oddities.

This abandoned dream castle and its cemetery look out over the city that once inspired their creation.

The largest burial mound in the United States holds the remains of prehistoric West Virginians.