At 135 years old and counting, this historic print shop is heaven for poster nerds and music buffs.

Prehistoric animals decorate this popular outdoor park.

The world's longest known cave system.

Once a bustling cotton factory, this early 20th-century building is now home to a thriving artspace.

The park is home to the United States's only still-operating Dutch windmill.

A tribute to the pop culture icon overlooks this Washington D.C. intersection.

The oldest building in the District of Columbia was preserved because of a mistaken connection to George Washington.

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

Sometimes called the “Little Golden Gate," this bright yellow structure is the last driveable suspension bridge in Arkansas.

This haunted hotel built on natural springs once served as a hospital for a quack doctor promising a cure for cancer.

An average of 33 million gallons of water pour out of the collapsed cave at the heart of this spherical spring.

A historic, scenic mill that was forced to close due to overlogging.

It's as if the herds walked straight out of a fairy tale into the Missouri wilds.

One of the deepest springs in Missouri.

Often referred to as the largest spring in America.

The maximum security facility was once thought to have "the bloodiest 47 acres in America."

Odd castle-like structures for collecting water sticking out of the Mississippi River.

A plaque on the side of a parking garage marks the burial place of a great Ottawa chief.

The eccentric and colorful pavilions of Tower Grove park are a beloved and overlooked symbol. 

This 45-story tall abandoned skyscraper is the third tallest building in New Orleans and Lousiana.

This Memphis recording studio launched the careers of Jerry Lee Lewis, Johnny Cash, and Elvis Presley.

This park offers a variety of sights and activities including trail rides and buffalo sightings.

Kentucky, Tennessee, and Virginia meet at this point in the Cumberland Gap.

This hands-on museum houses roughly 80 vintage pinball machines and arcade games.