I-8: Mission Valley Freeway / Kumeyaay Highway

Mission Valley Freeway / Kumeyaay Highway
Runs from Sunset Cliffs Blvd in San Diego to Winterhaven, CA and to Casa Grande, AZ (I-10)

High Points:

  • Laguna Summit – 4055′
  • Crestwood Summit – 4181′
  • Tecate Divide – 4140′


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Highway Videos by Forgotten Hwy:

This freeway serves as the sole freeway connection east for the San Diego area. Running from near the beaches, over a mountain range, and through the Imperial Desert, it is indeed a route with varied terrain. As a result of these differences, I-8 holds a couple of records for Interstates. It has the tallest bridge on the Interstate system, at 440′ above the canyon floor. It also has the lowest point on the Interstate system, at about -72 feet at the crossing of the New River near Seeley. The route, in California, follows former US 80 and was completed about 1975.

Taylor St at US 80 (Now I-8) in 1960, looking east, Courtesy – Caltrans
Original 1950's guard rail in Mission Valley near Taylor Road.
Original 1950’s guard rail in Mission Valley near Taylor St.
I-8 (then US 80) at Texas St in 1961. Courtesy – Caltrans
Fairmount Avenue and I-8 (then US 80) in 1961. Courtesy – Caltrans
Former “Map Stop” on westbound 8 in Blossom Valley. It has since closed.
I-8 from Japutal Valley Road toward Boulevard.
I-8 from Japutal Valley Road east toward Boulevard.
I-8 just east of East Willows Road showing an arrow in the middle lane. This was painted during freeway construction in 1972.
I-8 just east of East Willows Road showing an arrow in the middle lane. This was painted during freeway construction in 1972.
Walker Canyon looking east
Descending Mountain Springs Grade along the San Diego/Imperial County line.
Descending Mountain Springs Grade along the San Diego/Imperial County line.
In-Ko-Pah Gorge just below Mountain Springs. Roadway cut above the freeway is old US 80 pre-1940.
Scenic section of the Gorge.
Sea Level sign heading east near Seeley.
Lowest point on I-8 and the Interstate system – New River crossing at -72 feet.
Heading east along the “new” section of the 8 between State 98 and the Algodones Dunes. This section was reconstructed with new concrete around 2019.
Passing through the Sand Hills (Algodones Dunes)
Beneath the All American Canal bridges in the Sand Hills. Bridge on the left is originally from 1939 and was modified in the 1960’s. Courtesy – Casey Cooper

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