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

A castle built by an eccentric medieval enthusiast in rural Ohio.

This small plaza encourages people diagnosed with cancer to never give up hope.

Just outside the Ohio Supreme Court sits a testament to justice.

A bronze of the man in all his sinewy glory celebrates his longtime connection to the Ohio city.

This tea house was a hand-built gift from Boulder's sister city in Tajikstan.

One-time winter retreats of prolific inventor Thomas Edison and his friend Henry Ford.

The largest retailer of seashells in the world.

The ruins of the suspension bridge hang over Kingsbury Run as a ghost of racial prejudice.

Marvel at this turn-of-the-century masterpiece that has been turned into a rather stately supermarket.

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

What appears to be a wizard's lair in Milwaukee actually houses a massive water pipe.

This water tower slanted at an uncomfortable angle off the old Route 66 was an ingenious marketing ploy.

A small car graveyard sits in the shadow of the famous Cadillac Ranch.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

Mysterious Incan ruins on a tiny island in Lake Titicaca.

Visit a replica of the estate where Aaron Burr allegedly plotted a treasonous scheme against the United States.

Home to several unusual artifacts, including a huge painting of George Washington.

One of the few places where you can explore a 1918 paddlewheel steamboat from stem to stern.

Now abandoned, the first public health hospital in the U.S. saw more than one million immigrants from around the world.

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

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

Edgar Allan Poe's old dorm is now a shrine to the author's legacy.

One of corporate America's best-kept secrets is also one of the most publicly displayed.