T1S, R2E, undesignated section of Canada de Los Vaqueros Land Grant, Byron Hot Springs USGS 7.5' Quadrangle. Below the high water line of Los Vaqueros Reservoir, 1.4 miles northwest of Los Vaqueros Reservoir Marina, 1.9 miles (air) southwest of Los Vaqueros Reservoir Dam,, Contra Costa, California, United States, North America