A six-story treehouse offers spectacular views of New York's Finger Lakes region.

A castle built for love, and abandoned due to heartbreak.

Comprehensive gaming collection of over 30,000 electronic games and consoles.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

The absurd creation is a compulsory destination for selfies in Buffalo.

Oldest existing church in New York and the inspiration for Washington Irving's "The Legend of Sleepy Hollow."

Visit the monolithic tomb of America's most famous general.

In upstate New York, gorgeous waterfalls and a watermill are slowly being reclaimed by nature.

The first and only carousel with a lineup entirely of insects.

A natural gas leak provides a flickering flame beneath a waterfall.

A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.

Maryland's first (and last standing) toll house on America's first federal road established the state as the "Gateway to the West."

A star fort along the C&O Canal in western Maryland that protected America in three wars.

This one-room cabin where the young colonel slept during the French and Indian War.

George Washington's dentures and Queen Victoria's dental instruments are in the nation’s official museum of the dental profession.

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

This dig site outside D.C. is known for its exceptionally high density of baby dinosaur fossils and dinosaur eggs.

Despite violent work crews and massive delays this abandoned canal tunnel was built to last into the modern day.

The hide of Stonewall Jackson's equine sidekick is on display not far from where the ashes of his bones are buried.

At Washington's Dulles Airport is a satellite museum (no pun intended) with three quarters of a million square feet of aircraft history.

The story behind the mysterious symbol painted in front of the historic university's famous Rotunda.

This campus chapel is Robert E. Lee's final resting place and a topic of debate about the legacy of the Civil War.

Thomas Jefferson's estate is home to hundreds of varieties of historic fruits and vegetables.

Soldiers were buried next to Lee's house in the center of Arlington Cemetery to dissuade the general from reclaiming his property after the war.