The only natural lake in the world that drains into both the Atlantic and Pacific Oceans.

A miraculous natural phenomenon known as "the spring that breathes."

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

A beautiful geyser under environmental threat.

An unusually designed bridge from the 1920s was built to withstand the tides and winds of Maine.

This tiny patch of arid sand sits in one of the greenest states in the United States.

Developers built a Walmart around one family's plot and constructed a mausoleum in the parking lot.

The last holdout of a pre-Civil War rebel who took the matter of slavery into his own hands.

A table rock formation that has been intriguing West Virginians for years.

One day a year it is legal to jump off of this astoundingly tall bridge that spans an Appalachian gorge.

Built following the War of 1812, this fort has withstood hurricanes for centuries.

Built by prisoners of war, the largest small-scale model ever built includes eight miles of tiny streams that now sit abandoned.

This Florida sinkhole hides a rainforest-like micro-environment in its depths.

"Where the ducks walk on fish."

Behold the rickety wooden glory of the world's oldest operating roller coaster.

Contrary to what one might expect, ice forms inside this small cavern during the summer and melts during the winter.

This Pennsylvania cave holds evidence of the oldest known inhabitants of North America.

The universally beloved children's television figure is interred on a high hilltop in one of western Pennsylvania's oldest cemeteries.

"Dark Sky Park" is heaven on Earth for astronomers, one of the rare U.S. locations with no artificial light pollution.

Sail through this subterranean show cave that is home to a legend that would go on to name nearly everything around it.

An abandoned stretch of highway, deteriorating next to the operational one.

One man is on a singular quest to name an island after a famous hip-hop artist.