Northbrae Tunnel

The Northbrae Tunnel, also referred to as the Solano Avenue Tunnel, was built as a commuter electric railroad tunnel in the northern part of Berkeley, California, and was later converted to street use. In 1910 the Southern Pacific Railroad (SP) was electrifying its steam-engine drawn ferry-train line (to San Francisco) from Oakland Pier via Shattuck Avenue to Vine Street in Berkeley and extending it north along the base of the Berkeley Hills to newly developing neighborhoods of Berkeley at Northbrae and Thousand Oaks. The route chosen was Henry Street and Sutter Street to its intersection with Hopkins. At this point a ridge carrying Marin and Los Angeles Avenues blocked the way. After investigating (1) a route around the ridge and (2) a cut through the ridge with bridges over it, it was decided to use the route of the cut but make it a tunnel instead, under Marin and Los Angeles Avenues just west of their intersection with The (Marin) Circle. The cut-and-cover method of tunnel construction was used. The tunnel curved to the west so that the railroad could continue through to the intersection of Solano Avenue and The Alameda and then to Thousand Oaks station at Solano and Colusa Avenues. The line also required a level grade across the lower canyon of Codornices Creek. To accomplish this, a temporary wooden trestle was built along Henry Street with tracks for the construction t

Tunnel data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).