World's first "penitentiary," meant to be humane, drove men insane.

The highway's southernmost spot is a beloved local attraction.

The birthplace of American international flight service has been turned into a celebrity's microbrewery.

The island residents are known for taking their quirky sense of humor with them to the grave.

A monument celebrating the idea of reaching inaccessible places.

Florida's oldest bar was once a morgue, complete with a hanging tree and gravestones.

These remote Florida islands have a history of sea turtles and sunken treasures, and one of the world's largest coastal brick fortresses.

The former home of the Nobel Prize-winning American writer is now home to dozens of six-toed cats.

A dozen U.S. presidents have stayed at the historic resort, which was known as James Buchanan’s “Summer White House” from 1857-1861.

Home of the only civilian casualty at the Battle of Gettysburg.

This extraordinary Depression-era expenditure was modeled after a postcard of a Mediterranean hotel.

A preserved 18th century homestead in Western Pennsylvania marks the spot where the Whiskey Rebellion began.

Alexander Hamilton’s creation caused quite a bit of controversy.

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

What looks like a simple quaint estate in rural Pennsylvania was in the 18th century home to a small monastic community.

North America's oldest quarantine facility was built in response to Philadelphia's 1793 yellow fever outbreak.

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

Erected in 1697 this Philadelphia bridge is the oldest surviving roadway bridge and perhaps the oldest stone bridge in the United States.

Board a mine car and descend the #190 slope 300 feet underground into the Clark Vein of coal.

This little-known Revolutionary War fort is supposedly haunted by the ghosts of its past.

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.

The oldest surviving botanic garden in the United States.

A restored Pittsburgh house of God has been converted to a marvelous house of suds.

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