Maps of Napa County
Created from the U.S. Census Bureau's Tiger Map Server.
Further Reading
Beck, Warren A. and Ynez D. Haase. Historical Atlas of California. Norman, Oklahoma: University of Oklahoma Press, [1974].
Durham, David L. Durham's Place Names of California's Old Wine Country: Includes Napa and Sonoma counties. Clovis, California: Word Dancer Press, 2001. This gazetteer includes: "Thousands of topographic...and cultural features...Many entries include information about who named the feature, when and why, as well as alternate or obsolete names. A complete bibliography of sources is included."
Further Surfing
Interactive Map of Napa County
Google's interactive map service. For larger towns, you can zoom down to street level.
Official Map of the County of Napa, 1895
Two versions of a map that "shows drainage, roads, railroads, land ownership, township, section and quarter section lines, ranchos, political townships, school districts, etc." If your ancestor owned landed in Napa County in 1895, you should be able to find your ancestor's name on this map.