This project identifies areas of archaeological sensitivity for historic resources related to the segment of the South Pacific Coast Railroad that spanned from Los Gatos to Glenwood in the steep terrain of the Santa Cruz Mountains in Central California. The rail line was only in use for 60 years (1880-1940) until the completion of a major highway drew travelers to greater automobile use. During the construction and operation of the rail line, small towns sprouted at the railroad stops, most of which were abandoned along with the rail line in 1940. Some of these towns are now inundated by reservoirs. This project maps the abandoned rail line and “ghost towns” by using ArcGIS Pro (version 2.5.1) to digitize the railway, wagon roads, and structures shown on a georeferenced topographic quadrangle created in 1919 (Marshall et al., 1919). Through spatial analysis, an area of archaeological sensitivity was created that identifies where artifacts and features related to the railway and its associated towns from turn of the 19th Century are likely to be found.