Circa 1911, traffic between Los Angeles and Pasadena crossed the Los Angeles River on the congested North Broadway Bridge, the largest concrete bridge in California at the time. The Dayton Avenue Bridge provided another crossing to the north, but the hills of Elysian Park prevented it from being connected to downtown. The north three tunnels opened by November 1, 1931, connecting to North Broadway on the south via Solano Avenue and Riverside Drive on the north. Riverside Drive was an earlier high-speed road along the Los Angeles River to Burbank, and also intersected the Dayton Avenue Bridge, which led to Dayton Avenue (now part of Figueroa Street) towards Pasadena. From opening, the tunnels carried two lanes in each direction, with a 5-foot (1.5 m) sidewalk on the side.