Mountain Quarry Railroad Bridge, over the North Fork of the American River, is built out of reinforced concrete, the first of its kind. Finished March23 1912 the bridge is 482 Ft long, 15 FT wide and 70 FT high. It was out of service by the early 1940's.The failure of Hell Hole Dam in 1964 saw it use for transportation after the modern highway bridge failed.
