The famous abolitionist’s preserved estate is one of Washington's finest monuments to its great Black citizens.

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.

With over 100 jam-packed rooms to explore plus elaborate tea services and events, the Mansion on O Street is a hidden treasure.

A diorama of the Civil War, fought by cats.

This print shop boasts one of the largest pinball arcades in San Francisco.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

The origin of this mechanical boy was a mystery until he revealed his maker by writing it in perfect cursive.

The tomb was guarded by soldiers from both sides of the war, and some left their initials carved in the brick.

A granite monument honors a beloved World War II canine mascot.

Memorial built in 1922 in remembrance of WWI casualties.

The state's oldest continuously operating museum houses more than 5,000 Civil War artifacts.

The rusting remains are visible sticking out of the waters of the Delaware Bay.

World War II bunker still standing on the New Jersey beach.

Step inside Lucy, the world's largest "elephant."

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.

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

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 largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

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

The United States’s oldest funicular railway glides up and down a steep Pittsburgh street.

Sail through this subterranean show cave that is home to a legend that would go on to name nearly everything around it.

This prehistoric sinkhole lured exclusively male mammoths to their death, much to the delight of science.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

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