This monolithic statue was erected in honor of Chief Black Hawk (even if it wasn't made to look like him).

The resting place of a Civil War celebrity's amputated limb.

The Kirkland Monument remembers a selfless Civil War hero who braved the battlefield to give water to his dying enemies.

More than 5,000 contemporary and "historic" mustards from around the world.

An urban laboratory.

Officially named the "Loneliest Road in America," this barren stretch of Nevada road offers almost nothing but sky and open fields.

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.

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

The biggest solar telescope in the world helps reveal the secrets of our sun.

A science teacher's dream.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

The largest known Ancient Egyptian obelisk.

Ozymandias’ time-keeping temple.

A 56-foot tall statue of the god of fire looks out over Birmingham, Alabama.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.

The largest source of fossilized insects anywhere.

The only road through the heart of Glacier National Park.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

This raised bulls-eye visible from space was the subject of an intense geologic controversy.

Bizarre lunar-like landscape with thousands of large stone "hoodoos."

This Route 66 classic sports a giant fiberglass rabbit that you can ride.

A pair of giant roadside arrows are all that remains of a former Route 66 trading post.