From San Diego you'll ride on bike paths and residential streets on a steady climb into the mountains. Dry easterly winds predominate in the fall, blowing in from the central desert. At In-Ko-Pah Pass the route joins I-8 for a short distance. Calexico and Brawley are situated in the Imperial Valley, an area famous for its agricultural bounties. Stock up on food and water here; services are extremely limited on the next stretch of the route. SR 78 heading to Blythe carries a moderate amount of traffic. To the north you will see the Chocolate Mountains, named for their distinctive deep brown color. The terrain from Ehrenberg, Arizona, to the section's end at Tempe remains flat, with the exception of a few gentle grades. After leaving I-10, the route follows US 60 which has good shoulders. At Wickenburg the route turns south, then east as it approaches the metropolitan area surrounding Phoenix and Tempe. Click on enlargement for detail.