Gilroy is a city in Santa Clara County, California, United States. Gilroy is a city south of the San Francisco Bay Area, with a population of 59,520 as of the 2020 Census. Gilroy's origins lie in the village of San Ysidro, which developed in the early 19th century from Rancho San Ysidro. This land had been granted to Californio ranchero Ygnacio Ortega in 1809.