Take shelter from Hawai'i's tropical heat under the massive canopy of largest Banyan tree on the island.

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

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.

A stealthy Apache hideaway that became the haunting site of a mass grave.

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

If drivers cross the rumble strip on this stretch of Route 66 at just the right speed it plays "America the Beautiful."

More than 21,000 images fill this overlooked gem of a prehistoric site.

This is one really big nut.

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

A museum dedicated to the alleged Roswell Incident.

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

A Memphis park where you can walk the whole Mississippi River in one go.

Inside this museum resides a boot fit for a giant.

This museum glorifies the humble potato.

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

The first declared National Monument in the United States.

One man's ambition created this psychedelic log home.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

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

One of the largest collections of wildlife art in the United States, built into the side of a cliff in rural Wyoming.

This rustic old building is said to be the most photographed barn in America.

At the time of its completion, it was the tallest dam in the world.

The current Eureka County Courthouse replaced an all-wooden structure that had previously been an ice-skating rink.

This ancient village provides insight into the complexity of the pre-Columbian Fremont Culture.