The Sunset Tunnel, originally known as the Duboce Tunnel, is a 4,232 ft (1,290 m)-long light rail/streetcar tunnel in San Francisco, California. The tunnel runs under the steep hill adjacent to Buena Vista Park and is used exclusively by the N Judah Muni Metro line.
The western portal of the Sunset Tunnel
The N Judah entering the eastern portal of the Sunset Tunnel, at the border of the Castro and Western Addition districts
Sketch of Arnold's proposed Market Street extension (1913), with a Mission–Sunset Tunnel portal near Eureka & Market, per Plan 3
October 1921 study by City Engineer's office showing six proposed routes for a Sunset District Extension, including the selected Duboce alignment. Also note surface alignment along Grove, which included a short tunnel under Alamo Square.
The N Judah is a hybrid light rail/streetcar line of the Muni Metro system in San Francisco, California. The line is named after Judah Street that it runs along for much of its length, named after railroad engineer Theodore Judah. It links downtown San Francisco to the Cole Valley and Sunset neighborhoods. The line provides rail access to Golden Gate Park. It is the busiest line in the Muni Metro system, serving an average of 41,439 weekday passengers in 2013. It was one of San Francisco's streetcar lines, beginning operation in 1928, and was partially converted to modern light-rail operation with the opening of the Muni Metro system in 1980. While many streetcar lines were converted to bus lines after World War II, the N Judah remained a streetcar line due to its use of the Sunset Tunnel.
N Judah train on Judah Street at 19th Avenue in 2017
A Boeing LRV newly in service on the N Judah, entering the Duboce Portal on Duboce Avenue, in March 1980.
N Judah train entering the eastern portal of the Sunset Tunnel.