Interstate 805

Interstate 805 (I-805) is a major north–south Interstate Highway in Southern California. It is a bypass of I-5, running roughly through the center of the Greater San Diego region from San Ysidro (part of the city of San Diego) near the Mexico–U.S. border to near Del Mar. The southern terminus of I-805 at I-5 in San Ysidro is less than a mile north of the Mexican border. I-805 then traverses the cities of Chula Vista and National City before reentering San Diego. The freeway passes though the San Diego neighborhoods of North Park, Mission Valley, Clairemont, and University City before terminating at I-5 in the Sorrento Valley neighborhood near the Del Mar city limit.

Planning for I-805 began in 1956, and the route was officially designated in 1959 before it was renumbered in the 1964 state highway renumbering. Starting in 1967, the freeway was built in phases, with the northern part of the freeway finished before the southern part. I-805 was completed and open to traffic in 1975. Named the Jacob Dekema Freeway after the longtime head of the regional division of the California Department of Transportation (Caltrans), I-805 has been frequently cited for its complex engineering and architecture, including near I-8 on the Mission Valley Viaduct. Since then, several construction projects have taken place, including the construction of local and express lanes at the northern interchange with I-5. High-occupancy toll lanes are under construction on both the northern and southern portions of the route.