Explore more than 130,000 new and used books in the "world's largest outdoor bookstore."

A popular winter vacation destination for migrating monarch butterflies.

A trail weaves through the verses of a poem illustrated by stone sculptures inspired by Native American pictographs.

Odd stone and concrete monuments in the "Poet of the Sierras" eclectic folly garden.

A promotional sun clock on the site of San Francisco's great raceway.

Golden Gate Park's historic collection of plants.

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

This erect, phallic geological spire wasn't always named so domestically.

Home to the world's largest quilt collection dating from the 1600s through today.

A black cottonwood gets a second life as a home for books.

A petroglyph map of the upper Snake River carved by prehistoric hunter-gatherers.

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

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.

The first declared National Monument in the United States.

A waterfall 600 ft. inside a mountain, once the bane of gold miners, is now a spectacle of nature.

Yes, this monument is aware that it is about 20 miles away from the actual center of the United States.

A striking sculpture built to honor the women of the Lakota and Dakota Nations.

A fitting attraction for the corn capital of the world.

This replica stave church looks like a piece of Norway was simply plopped down in South Dakota.

A roadside collection of over-sized iron creations that are a bit more macabre than most.

The granddaddy of all tourist traps, built on ice water, jackalopes, and a giant dinosaur.

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