Digital geospatial data sets for two maps (Plate 1, Elk River watershed, Humboldt County, California, geologic and geomorphic features related to landsliding; and plate 2, Elk River watershed, Humboldt County, California, relative landslide potential with geologic and geomorphic features). These maps portray landslides, geomorphic features related to landsliding, relative landslide potential, geology, and stream channel geomorphic conditions in the Elk River watershed, Humboldt County, California. The GIS data are organized into four groups: landslide layers; geomorphology layers; fluvial layers; geology layers.