See massive fossils that are over 200 million years old in northeastern Arizona.

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

This site is home to ancient petroglyphs and pictographs dating back to 6,000 B.C.

Although it also features red, orange, and variegated cliffs of Navajo Sandstone, this state park is often overshadowed by its more famous neighbor.

At this gas station in the middle of the desert, a convenience store has been carved directly into the rock.

The unusual patterns in this rock formation result from two distinct modes of weathering.

The notorious Wild West outlaw was raised in this unassuming abode.

A tunnel with windows, so you don't miss out on the impressive views.

The fifth-longest natural arch in the world, and the longest outside China.

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

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

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

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

An abandoned quicksilver mining town surrounded by the Big Bend parks.

Kentucky, Tennessee, and Virginia meet at this point in the Cumberland Gap.

The site of Paul Revere's historic two lantern warning.

A copy of the famous bus used during the filming of 'Into the Wild' is on display at an Alaska brewery.

14th century Norse artifacts in Northwestern Minnesota could have proved a Viking landing before Columbus.

One of the few working locomotive roundhouses in the United States.

This lighthouse and shipwreck museum keep a torch burning for the memory of the SS Edmund Fitzgerald.

Unique Michigan homes look like something out of Tolkien's "The Lord of the Rings."

Walk up a ramp through a forest for panoramic views of Lake Michigan.

The site of an ancient Mississippian settlement that appears to have flourished during the 10th to 13th centuries.

One of the largest aviation events in the world brings half a million aircraft enthusiasts to Wisconsin each year.