Rare recess caves fill this unbelievably beautiful Ohio park.

A fitting attraction for the corn capital of the world.

The largest earthwork effigy in the world.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

It houses the remains of a 17th-century version of the Titanic.

Rediscovered after a century, the father of the American Navy was reinterred in something dredged up from Davy Jones’ locker.

This beautiful stone arch bridge wasn't even expected to stand for one day, but people have been crossing it for centuries.

A rare chance to get up close and personal with a 13-mile ribbon of ice near downtown Juneau.

This kitschy tavern is also home to rare early editions of "Treasure Island."

Cleveland's giant "free" stamp is a nod to the Civil War, but was misinterpreted for years.

An unusual round church in London with a Templar past.

A plain wooden seat that once belonged to one of the most prominent figures of the Protestant Reformation.

You can find America's highest suspension footbridge at Grandfather Mountain in North Carolina.

This pair of eccentric Ohio castles were built by a pair of brothers who wanted to bring a bit of class to the Ohio wilderness.

An early-19th-century hotel with a past that is steeped in the Civil War.

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

Every president in history is immortalized in bronze in downtown Rapid City.

A grandiose octagonal home crowned by a large dome stands out among the antebellum mansions.

The second-largest ceremonial mound in the United States is an artificial hill that is loosely shaped like a pentagon.

This 600-year-old home seems to defy physics.

This replica of the Greek structure is in the heart of Nashville.

This black shoreline is made up of exploded lava particles.

The world's smallest drawbridge.