As it continues northward through Sonoma County, it meets SR 116, where it then veers east.

As it leaves the city, it continues northward for several miles before reaching its north end at SR 128 near Lake Berryessa.

The northern section, however, was slightly altered since its definition the same year due to a realignment of various other freeways.

[8] Except where prefixed with a letter, postmiles were measured on the road as it was in 1964, based on the alignment that existed at the time, and do not necessarily reflect current mileage.

[1] Segments that remain unconstructed or have been relinquished to local control may be omitted.