The only presidential monument to display a late POTUS's actual casket.

This scenic Maryland park was the site of one of the worst prison camps of the Civil War.

The highest point in Delaware is located under a trailer so this marker across the street will have to do.

As state high-points-by-elevation go this spot is one of the lowest, but for years it was also the hardest to climb.

Don't get it twisted: This is the oldest pretzel bakery in the United States.

A near tragic event on this bridge helped inspire the classic film "It's a Wonderful Life."

A deteriorating 1990s Girl Scout camp in a beautiful lush park on Lake Ontario.

The highest point in Connecticut was incorrectly memorialized before surveyors discovered the actual spot.

Inspiring Herman Melville and Henry David Thoreau, Mount Greylock in western Massachusetts is the highest point in the state at 3,491 feet above sea level.

A statue honoring 44 continuous years of greeting passing ships.

This ancient Hawaiian henge may have been an early star chart.

This group of small islands on Lake Nicaragua formed after an eruption of the Mombacho volcano.

A historic landmark and museum filled with curious objects representing the history of Key West.

A historic presidential getaway on the continental United States' southernmost island.

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

A monument celebrating the idea of reaching inaccessible places.

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

The house that Frank Lloyd Wright "(shook) out of his sleeve at will" at the age of 86.

Frank Lloyd Wright's most iconic home dangles over a Pennsylvania waterfall.

Pennsylvania's highest point is spotted with boulders which were pushed to the surface by nothing but cold.

This giant, rotating globe was built to celebrate the expansion of a company that makes steam cleaners and pressure washers.

This titanic java kettle is one of the many kitschy landmarks located along America's OTHER famous highway.

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

Built by the patriotic residents of Boonsboro in a single day.