Shoshone sits on the Snake River Plain in south-central Idaho, a flat, dry, lava-floored country of sagebrush, irrigated fields and enormous skies, and it is the county seat of Lincoln County, with about fifteen hundred people. Its stone buildings date from the days when the railroad arrived, in the 1880s, and the town was a junction where cattle and sheep were shipped. The courthouse and the old storefronts have a worn, dignified look, and the whole place has the unhurried air of a town that has seen a lot and seen it go by.
The ground beneath is volcanic. The plain is a vast sheet of basalt laid down by eruptions over millions of years, and it is full of lava tubes, caves and cracks, some of which hold ice year-round. Not far away, Craters of the Moon National Monument shows the landscape in its rawest form, a field of black lava, cinder cones and spatter cinders. To the south, near Twin Falls, the Snake River drops over Shoshone Falls, a waterfall higher than Niagara, often called the Niagara of the West, which is at its best in spring.
The Sawtooth Scenic Byway begins here and heads north on US 93 and then Highway 75, through the Wood River valley and the resort towns of Hailey and Ketchum, then up over Galena Summit, at about eighty-seven hundred feet. The country changes from desert to mountains as you ride, with the road gaining height through sage, then aspen and pine, until the pass opens a view of the Sawtooth Valley, with its jagged ridge above. The surface is good, with long straight sections early on and winding bends after Ketchum.
Fuel and supplies are available in Shoshone, so fill up before the ride, since there are few services on the long road across the plain. Jerome, about twenty-five kilometres to the south, is a larger town with more choices. Summers are hot and dry, with thunderstorms, and winters are cold. Wind can be strong, and dust blows across the flats. The best seasons for the ride are late spring and early autumn, when the weather is milder and the light is clear.