The only natural lake in the world that drains into both the Atlantic and Pacific Oceans.

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

The high point on the 16th president's eponymous roadway is marked by a massive version of his head.

An architect's childhood fantasy treehouse made real.

One man's ambition created this psychedelic log home.

The first declared National Monument in the United States.

This church on a Tohono O'Odham reservation has stood since 1797.

Take a monster truck tour around an ostrich farm in the middle of the desert.

This immigrant bridge once spanned the Thames but is now a fixture of an Arizona city.

Walk through the actual strap iron cells and solitary chambers of Arizona Territory’s first prison.

What is the Thing?

The world's largest military aircraft cemetery.

Some of the tallest ancient American ruins continue to inspire awe and curiosity.

America's only nuclear missile silo open to the public.

The first permanent memorial to a unique secret weapon of World War II.

Three hundred years of preserved Spanish colonial history in San Antonio.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

A fitting attraction for the corn capital of the world.

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

A place where the laws of nature seem to have gone completely berserk... but of course haven't.

A six-ton, 12-foot-tall concrete prairie dog is touted as the largest in the world.

One of the first intercontinental ballistic missile sites in the United States.

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

Locals place their offerings on this nightmarish gnarled tree so the witches won't summon another storm.