Carpenter Summit

Carpenter Summit is a highway pass name approved through the United States Geological Survey. This pass was created during the construction of I-8 from 1972 to 1974 in this area, but was never named unlike the three other 4000 ft then named during construction. The name “Carpenter Summit” was proposed in late 2019 then submitted and as of October 2020 pending the various levels of place name acceptance.

This highway pass is the first of four which were completed through the Cuyamaca Mountains of southeastern San Diego County, California and traversed by Interstate 8 East bound at an altitude of 4052 ft and West bound at 4078 ft. The freeway is divided at this location by an east–west ridge with a peak of 4120 ft.

Google Street view of I-8 East bound 4,000 foot elevation sign. Google Street view of I-8 West bound 4,000 foot elevation sign.

Of the four 4000 ft highway summits eastward of San Diego, the Laguna Summit is the second. The third is Crestwood Summit followed by the Tecate Divide.

Construction
The Interstate 8 route was realigned from Arnold Way onto Alpine Boulevard as it passed through Alpine and the Viejas Indian Reservation, before entering the Laguna Mountains and the Cleveland National Forest mostly paralleling the alignment used by old US 80.

By August 1970, the remainder of the freeway had been funded in this area, with the part from Japatul Valley Road to Laguna Junction costing $22 million (about $ in dollars), (about $ in  dollars).

By the beginning of 1974, the new projected completion date for this I-8 section was mid-1975, with 22 mi of two-lane highway remaining. The new Pine Valley Creek bridge and the segment extending from Japatul Valley Road to Pine Valley was dedicated on November 24, 1974, and was scheduled to open on November 26; this left 8 mi of freeway to be constructed. The final stretch of I-8 in California, from Sunrise Highway to La Posta Road, was completed in May 1975.