Interstate 680

Dublin California

Interstate 680(I-680) is Northern California’s major north-south Interstate Highway. It curves around San Francisco Bay Area’s eastern cities from San Jose to Fairfield’s Interstate 80, bypassing cities along San Francisco Bay’s eastern shore like Oakland and Richmond while serving other more inland cities like Pleasanton and Concord. Constructed in the 1920s and signed in 1955,I-680 begins at a junction withI-280 and US 101 (Bayshore Freeway) and passes northeast and northwest through San Jose’s northeast portion. Upon passing State Route 237 (SR 237) in Milpitas and SR 262 in Fremont,I-680 suddenly turns northeast (where a connection is intended to an SR 238 freeway) and enters the California Coast Ranges hills and valleys. Crossing Mission Pass, also known as the Sunol Grade, the highway goes down into the Sunol Valley, where it reaches SR 84 near Sunol. From Sunol,I-680 continues northwest again through valleys along the Calaveras Fault, including the San Ramon Valley. in Dublin and SR 24 in Walnut Creek are junctions along this section. Beyond the latter intersection, a three-way junction with the SR 24 freeway west to Oakland,I-680 heads north to Pleasant Hill, where SR 242 separates andI-680 heads northwest again. The highway crosses the Carquinez Strait on the Benicia-Martinez Bridge after the intersection with SR 4 in Martinez, immediately entering the east end of I-780 at the end of Benicia. The rest of I-680, from Benicia to Fairfield I-80, stretches between a hilly area to the west marking the southwestern tip of the Vaca Mountains and a marshy area to the east (along the Suisun Bay and Cordelia Slough). The path begins in the U.S. Route 101 at the Joe Colla Interchange, where it acts as a continuation ofI-280 eastward.[4] From here it begins its path north through San Jose, where it reaches the Capitol Expressway, signed as CR G21, about a mile north-east of the southern terminus of I-680.[2] The next exit northbound is SR 130, also known as Alum Rock Road, not marked at the intersection. It crosses numerous local roads before interchanging with the Montague Expressway as it travels through Santa Clara County. It leaves San Jose here and enters Milpitas, California, where it crosses SR 237, also named Calaveras Boulevard. leaves Santa Clara County after another intersection and enters Alameda County.