This geothermal hot spring hides beneath a slowly growing mineral dome.

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

Here, at the "world's longest art gallery," you'll find forty miles of ancient petroglyphs and pictographs.

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

This Philly landmark has a giant butterfly pavilion, three floors of insect displays, and withstood a $40,000 heist.

The train collection of an eccentric New England seafood mogul is now a National Historical Site.

A well-preserved example of an early industrial operation in the northeastern United States.

The lasting remains of the region's once booming cement industry.

A park in a small Pennsylvania town is home to an original sculpture by one of its native sons, legendary artist and activist Keith Haring.

An Olympic hero stripped of his medals is buried in a town he never visited, which took his name after his death.

Frank Lloyd Wright built this suburban synagogue late in life, but it stands among his most iconic masterpieces.

This Art Deco service station has been providing tune-ups and turning heads for close to a century.

Narrow gorges and deep pools created by long-ago glaciers.

This strange, big-tailed beast became a Pennsylvania town's unofficial mascot.

A pride of the state, this working museum crafts pottery mosaics in the style of Pennsylvania's earliest European settlers.

A giant ball made from pieces of an old Jeep.

One of the oldest log cabins in America is one of the last of its kind this historic Swedish dwelling remains a piece of living history.

Steepest flood safety railway in the entire world.

An almost life-sized elephant named Ms. Ellie greets visitors at this jumbo-themed museum.

A tradition unlike any other, this marks the site of the annual Groundhog's Day tradition.

This stone tower marks a lookout point over the historic Washington Crossing, and maybe some buried treasure.

A field of nothing but boulders which resembles a giant's gravel driveway.

One of the U.S. Forest Service's only mansions is outfitted with a dinner table for floating food.

This jail which was in service for over a century is now open for curious visitors.