This part of DS 781 presents data for the bathymetry map of the Offshore Half Moon Bay, California. The raster data file is included in "Bathymetry_OffshoreHalfMoonBay.zip," which is accessible from https://pubs.usgs.gov/ds/781/OffshoreHalfMoonBay/data_catalog_OffshoreHalfMoonBay.html. These data accompany the pamphlet and map sheets of Cochrane, G.R., Dartnell, P., Greene, H.G., Johnson, S.Y., Golden, N.E., Hartwell, S.R., Dieter, B.E., Manson, M.W., Sliter, R.W., Ross, S.L., Watt, J.T., Endris, C.A., Kvitek, R.G., Phillips, E.L., Erdey, M.D., Chin, J.L., and Bretz, C.K. (G.R. Cochrane and S.A. Cochran, eds.), 2014, California State Waters Map Series—Offshore of Half Moon Bay, California: U.S. Geological Survey Open-File Report 2014–1214, pamphlet 37 p., 10 sheets, scale 1:24,000, https://doi.org/10.3133/ofr20141214. The bathymetry map of the Offshore Half Moon Bay, California, map area was generated from bathymetry data collected by Fugro Pelagos, and by California State University, Monterey Bay (CSUMB). Mapping was completed in 2006 and 2007, using a combination of 400-kHz Reson 7125 and 244-kHz Reson 8101 multibeam echosounders. These mapping missions combined to collect bathymetry from about the 10-m isobath to beyond the 3-nautical-mile limit of California's State Waters. These data are not intended for navigational purposes. NOTE: the horizontal datum of the bathymetry data (NAD83) differs from the horizontal datum of other layers in this SIM (WGS84).