Hill Street Tunnel
Hill Street Tunnel referred to a series of rail and road tunnels in Los Angeles, California. Initially constructed to bypass the grades of the street's namesake Bunker Hill, one bore of the dual-bore tunnel served as the roadway of Hill Street while the other facilitated streetcars and interurban trains via a double track dual-gauge railway. One tunnel ran between Temple and 1st Streets. The rail bore was built by the Los Angeles Pacific Railroad and was opened for traffic on September 15, 1909. The company rebuilt five miles (8.0 km) of their track as standard gauge the night before the tunnel's opening.