Tour the world's largest deep-hole dimension granite quarry, where you can view the plant where gravestones are made and roll a ball down the outdoor granite bowling alley.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

Knoxville’s architectural icon was the symbol of the 1982 World’s Fair, even catching the googly eye of Bart Simpson.

The only statue of its kind to commemorate Washington's beginnings as an officer of the British Colonial Militia.

A living maritime paradox still floats in the same lake where it was built and resurrected... or was it?

A tour de force of a fountain, memorializing a man who loved fountains more than anything else.

These lush botanical gardens employ the most purrfect pest control force.

A daily replay of the experiment that proved the rotation of the Earth.

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

The body of St. John Neumann and his collection of hundreds of relics, on display in a Philly church.

A local prank turned town icon.

This elaborate towering structure was once famed for its revolutionary height.

An indoor miniature village and labor of love for Laurence Geiringer, a model railroad enthusiast.

A failed piece of Orientalism has become the proud symbol of a community.

The first American department store, and home to the largest operating musical instrument in the world.

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 charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

A toxic ghost town sitting atop a massive coal fire.

The oldest operating Mississippi River–style steamboat still navigates the Ohio River.

The world's longest known cave system.

Illegal drag racing two stories beneath Chicago’s streets.

The walls of America's oldest masonry fort famously "swallowed" cannonballs.

This small museum gives visitors a chance to soak up the history of the "sponge capital of the world."

Location of a reliquary containing bone fragments of 18 saints.