Spreading north of old Route 66, more than 1.6 million acres between I-40 and I-15 have been set aside as the Mojave National Preserve, a harsh desert landscape of volcanic cinder cones and sand dunes, desert tortoises, and Joshua trees. One evocative landmark here in the middle of the desert is the Kelso Depot (760/252-6100), a restored train station that sits on the main LA-to-Las Vegas Union Pacific Railroad line. Trains still rumble past, and the depot, featuring a variety of interpretive exhibits, recreates the sense of life here in the 1920s, before air-conditioning and cell phones made life in the desert so much more agreeable. Kelso is on Kelbaker Road, about 22 miles north of I-40, midway between Fenner and Ludlow.

Another of the many places in the Mojave Preserve that’s worth the trip is Mitchell Caverns (760/928-2586) at the center of Providence Mountains State Recreation Area, 25 miles north of I-40 at the end of Essex Road. At the time of this writing, the park was closed due to infrastructure issues. Call before you make the drive.