The longest continuous lava tube in Oregon.

The eerie remnants of an ancient forest were hidden under the sand for centuries.

The second largest waterfall by volume in the U.S., Willamette Falls is outdone only by Niagara in the amount of water that is pushed northward.

No one knows how this Pacific Northwest spruce tree came to have so many trunks.

These old stone ruins in the Oregon wilderness were once bathrooms and are steeped in legends of murder.

On the Oregon coast there is a natural hole that seems to be draining the sea.

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

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

Modeled after the labyrinth in Chartres Cathedral, this small-town Indiana memorial labyrinth sits half a world away.

Nature and art meet in this curvy creation

A hidden network of subterranean passageways lies tangled beneath Indianapolis' bustling City Market.

Once adorning a New York skyscraper, these reclaimed ruins now haunt an Indiana park.

The site of a 19th century "dream city" that almost rivaled Chicago before being swallowed by the Indiana sand dunes.

A vast collection of rare books, manuscripts & extraordinary objects illustrating the history of medicine.

While many places make the claim, the Library of Congress says this restaurant is the birthplace of the hamburger.

Yale University's home for rare works, including the mysterious Voynich Manuscript.

The only geyser in the state of Pennsylvania is caused by pressure from an abandoned coal mine outside of the ghost town Centralia.

Kentucky's anomalous peninsula projecting into the Mississippi River, site of legendary earthquakes and local feuds.

An enormous goose sits atop this nest-shaped home.

This once-private estate is now a dreamy, meditative garden that's open to the public.

The Hudson River School comes alive at this palatial estate.

For over 80 years, Mayan ruins stood proudly in a most unlikely location.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

Friction between grains of sand cause a curious "singing" sound.