A former major munitions plant that has been converted into a sprawling art space.

An alley covered with 20 years of bubble gum.

The ghostly remains of an accidental sea.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.

The lowest point in North America is home to an undrinkable pool surrounded by fields of geometric salt flats.

Spectacular views await visitors to this lake.

The decorations were inspired by an unlikely missing treasure.

This inanimate goat created by the "welding nun" has been helping to clean up the city of Spokane for more than 40 years.

Home to the deepest rift anywhere on Earth.

World War II bunker still standing on the New Jersey beach.

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

The branches of this sprawling cedar tree are laden with wishes big and small.

One tiny triangular park commemorates the victims of a yellow fever epidemic—many of whom are buried right below the grass.

An out-of-the-way wildlife haven with a rich and storied past of harboring thousands of fugitive slaves, or "Maroons" during the mid 1800s.

Collecting 700 years of mechanical death-dealing, the NRA's sprawling gun museum is a revealing testament to the American obsession with armament.

The U.S. Navy’s preposterously detailed mini battleship took 77,000 hours to complete.

The innocent intentions of this monument are somewhat lost in the sculpture's muscled imagery.

Look closely and you’ll notice that the color changes a third of the way up the tower.

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

Nuclear waste dump site now an environmental sanctuary.

This rare example of a "tidefall" is a spectacular drop from the cliffs down onto the beach.

The rusting remains of the largest assembled WWII fleet on the West Coast.

The cultural center preserves the history of the Tlingit tribe, who have lived in this Alaska village for more than 10,000 years.