The Bruneau Dunes are perhaps the most bizarre natural phenomenon in the state. Trapped in a low-laying basin just south of Mountain Home, they're thought to have originated during the Ice Age, in the aftermath of the Bonneville Flood. Unlike most sand dunes, those at Bruneau don't shift dramatically with the wind. They're trapped in the basin, and the highest peak stays at about 470 feet year-round.
In 1955, tiny Arco won fame as the world's first nuclear-powered city. Today, it mainly serves as a jumping-off point for excursions into the nearby Craters of the Moon National Monument. Arco is one of Idaho's strangest little towns, although nearby Atomic City manages to be even stranger. And littler.
Comprising 618 square miles of other-worldly lava-formed landscape, the Craters of the Moon National Monument is one of the strangest geographic areas in the entire country. Harsh, dry and largely barren, this craggily beautiful region has remained largely untouched by a humanity that never figured out a use for it. We visited one morning in late October, after a light layer of snow had covered the ground.
After an extended stay in Sun Valley, we got back on the road. Destination: Arco. We took Highway 26, which is also known as the Peaks to Craters Scenic Byway. It couldn't be more perfectly named. The picturesque aspen-covered mountains of Sun Valley slowly give way to the bizarre lava-formed landscape of the Craters of the Moon National Monument. We were lucky to have stunning weather during the drive: a perfect showcase for Idaho's stunning natural diversity.