National Register of Historic Places in Marin County
In 1925, the Good Roads Movement of Marin County passed a bond to upgrade 96 miles of roads, bridges and culverts. Included in the upgrade was the transformation of a crude wagon road known as the San Rafael Trail into Sir Francis Drake Boulevard to facilitate vehicular traffic between suburban eastern Marin and rural western Marin. The concrete Tocaloma Bridge replaced a wooden bridge.
The Tocaloma Bridge is a rare example of a reinforced concrete, through arch bridge in California. There are only seven in the state, and two are in Marin County - the Tocaloma Bridge and the Alexander-Acacia Bridge. Arched bridges were typically constructed as showcase bridges because of the expense. (All of the other bridges on Sir Francis Drake Boulevard are unremarkable slab bridges.)
In 1964, the county replaced the historic bridge with a new concrete span because the original westbound approach had a hazardous curve. The old bridge became a pedestrian bridge on a hiking trail.
Adapted from the NRHP nomination submitted in 2018.