This is an 1859 Plat map of the Novato Rancho, one of the original Land Grants that divided what we now know as Marin County. Plat maps were created to show survey information about area, divisions and boundaries of a piece of land, being sold or transferred. Most early Plat maps showed boundaries as running "from Laurel tree, NE, 47 chains to High peak, E 15 degrees S, 36 chains to..." etc. Once completed and approved by a local governing body, they became legal documents.
Text by Bill Damon.