Bommer Canyon is a roughly 4,000-acre open space preserve in southern Irvine, California, valued for trails through oak and sycamore groves, rock outcrops, and an unusually undeveloped landscape within an urban area. Its land was part of Rancho San Joaquin, established in 1837 by José Antonio Andrés Sepúlveda, and later became part of the Irvine Ranch under James Irvine. From the late 1800s to the 1970s, the canyon’s Cattle Camp was the center of the Irvine Company's cattle operations, and a preserved section still reflects that ranching past. Since city acquisition in 1981 and 1982, the canyon has gained recognition for recreation, conservation, and its natural heritage.