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

The site of America's first commercial oil well essentially disappeared after the town went bust.

The Pennsylvania landscape depicted by a quarter mile of mosaics made from used road signs.

Where the oil industry began.

The only statue of its kind to commemorate Washington's beginnings as an officer of the British Colonial Militia.

A quirky collection of outsider art made from automobile parts.

The final resting place of an unidentified revolutionary soldier sits behind a Virginia church.

The romance of early commercial flight still fills this Art Deco destination.

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

This isn't your average roadway—it's actually a National Park and a transportation pioneer.

The only place for a truly presidential dram.

The graveyard holding the remains of George Washington's slaves was forgotten for nearly 200 years.

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.

The rogue roots are gradually consuming some of the historic marble grave markers.

At 207 feet, one of the world's longest continuous escalators.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

This museum devoted to the gothic author holds such interesting ephemera as his socks and walking stick.

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

The longest escalator in the Western Hemisphere takes over three minutes to ride down.

The land is home to swimming ponies and a legendary 18th-century treasure.

The 28,000-year-old specimen is remarkably intact.

The innocent intentions of this monument are somewhat lost in the sculpture's muscled imagery.

The first memorial dedicated solely to the Black troops who fought for the Union.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.