No. 1051 Mountain Quarries Railroad Bridge spans the American River on the boundary between Placer and El Dorado Counties. Built in 1912, it was a very early example of reinforced concrete railroad bridge construction. The bridge was designed by John B. Leonard, a pioneer in the design, engineering and promotion of reinforced concrete construction. From 1912 until 1942, the Mountain Quarries Railroad operated trains over the bridge, carrying loads of sandstone from the nearby quarry to Auburn, California where MQRR met the Southern Pacific Railroad.
Trailhead on Hwy 193/49, just east of Old Foresthill Rd. Bridge spans American River.
We parked at the trailhead on Hwy 193/49, just east of Old Forest hill Rd. Bridge spans American River. We took the trail that runs on the NE side of the American River. Then we crossed the bridge to get to the plaque. It would have been a short and easy stroll in the shade if we had parked on HWY 49 just south of the river and entered through the gate on Hwy 49. See the pictures.