There are 28 routes assigned to the "A" zone of the California Route Marker Program, which designates county routes in California. The "A" zone includes county highways in Lassen, Plumas, Shasta, Siskiyou, and Tehama counties.
There are 28 routes assigned to the "A" zone of the California Route Marker Program, which designates county routes in California. The "A" zone includes county highways in Lassen, Plumas, Shasta, Siskiyou, and Tehama counties. (en)