While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

The "lovely red Vega" of the legendary record-settling pilot.

There’s a hidden military meme engraved on the World War II Memorial.

A gift from Japan, 17th-century lantern stands among the cherry trees at D.C.'s Tidal Basin.

An overlooked memorial honoring the local Washington residents who died in World War I.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

The Lincoln Memorial has inspired many, even though a word on the inscription appears to be spelled incorrectly.

This is the spot where the bloodiest battle in the American Civil War may have started.

This covered bridge was used by both Union and Confederate troops during the Battle of Gettysburg in 1863.

This Civil War monument was designed by an eccentric architect and Gettysburg veteran.

This monument marks the beginning journey of a wounded soldier's leg that ended up almost two states away.

Experience the pivotal Civil War battle at this interactive museum.

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

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

This Pennsylvania structure, the oldest building in Gettysburg, was once a stop on the Underground Railroad.

A diorama of the Civil War, fought by cats.

The "world's biggest dinosaur" once housed a creationist museum in its abdomen.

Megachurch turned Catholic church comprised of 10,000 glass panes.

The lead horse on a Disneyland merry-go-round that is older than the park itself.

Allegedly haunted by Walt Disney himself, this inconspicuous lamp is always kept lit in his honor.

Inspiration struck on this seat outside the Griffith Park merry-go-round.

The awe-inspiring ship from the golden era of cruising has an incomparable history and a reputation as one of the world’s most haunted places.

This spectacular track has run continuously since 1882.

The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.