Before reaching Pacifica, the highway travels through a treacherous stretch where it is dubbed Devil's Slide. Here the road is in constant danger of sliding into the Pacific Ocean. This stretch of road has been closed indefinitely since April 2, 2006 due to damage under the roadbed from rain saturation. Caltrans says extensive work needs to be done to stabilize the hillside, making the reopening around September of 2006. To avoid these problems, a tunnel is being constructed to bypass the slide area, opening in 2011 according to Caltrans.
After entering Marin County, Highway 1 then splits from US 101 again near Marin City, where it, now as the Shoreline Highway, returns to a winding, two lane road as it goes through the coastal cities of Bodega Bay and Fort Bragg. The highway then terminates at US 101 in Leggett in Mendocino County. - http://en.wikipedia.org/wiki/California_State_Route_1