North Gate Rd, Mount Diablo, CA

North Gate Rd starts in Walnut Creek, CA at the city’s edge, but ride just a few miles and the suburban sprawl drops away beneath you. You are on the climb to the summit of Mount Diablo.

The transition is immediate. Suburban streets give way to an engineering marvel carved into the golden, oak-studded hillsides of the East Bay. (crazy green in springtime!) The asphalt sweeps upward, tracking along massive ridgelines that offer increasingly panoramic views of the Diablo Valley.

North Gate Rd is a rhythmic mix of sweeping curves and steady elevation gain that tests your focus and rewards your eyes. After several miles of smooth carving, the road hits the Junction Ranger Station, where it meets South Gate Rd. From here, the real work begins on Summit Rd; the pavement narrows, the technicality ramps up, and the views become staggering as you wrap around the mountain's rocky face. Very trees here to block the view, it's wide open views.

The climax of the ride bicyclists call "The Wall"—a formidable 15% gradient final pitch that welcomes you to the 3,849-foot peak.

Standing at the 1939-era stone visitor center, the reward is unmatched. On the right day—without the haze—you are treated to a legendary, unobstructed view that stretches across the Central Valley all the way to the Sierra Nevada Range.

On the absolute clearest of days—usually during the crisp mornings immediately following a heavy winter storm—the line-of-sight visibility from the summit is staggering, reaching 150 to 200 miles in certain directions.

This extreme visibility is largely because Mount Diablo rises so sharply out of relatively flat, low surroundings, creating an incredibly vast visual footprint (a viewshed of roughly 13,000 to 21,000 square miles). On a perfect day, your field of view encompasses parts of 35 to 40 of California's 58 counties.

For the descent, head back down via the southern route on Mount Diablo Scenic Blvd. If you have time to explore, you can circle the base of the mountain by connecting Morgan Territory Rd to Marsh Creek Rd.