Scenic Interstate 680

Interstate 680's scenic segments cross Mission Pass, known locally as the Sunol Grade, before descending into the Sunol Valley near the historic Niles Canyon. The freeway is eligible for California's State Scenic Highway System along its full run from the Santa Clara-Alameda county line to State Route 24 in Walnut Creek, but only two shorter stretches, from Mission Boulevard to the Contra Costa county line and from the Alameda county line to Route 24, actually carry the official scenic designation. Just to the west, State Route 84 threads through Niles Canyon, a narrow, twisting stretch of the Sunol Valley so distinct it's treated almost as its own place name; a 7.1-mile section of Niles Canyon Road between Mission Boulevard and I-680 carries its own separate scenic highway designation. Together the two routes bracket one of the East Bay's more dramatic natural passes, where hills close in tightly around both the freeway and its older, narrower two-lane neighbor, giving drivers a choice between a fast crossing on 680 or a slower, more scenic detour through Niles Canyon on 84.

• Sunol Grade (Mission Pass)
• Sunol Valley
• scenic: Mission Blvd to Contra Costa line; Alameda line to SR-24
• connects to SR-84 near Sunol
• Niles Canyon (SR-84, 7.1 mi scenic)
• East Bay hills crossing