Peters Canyon in Orange County, now preserved as a 354-acre regional park within Orange and Tustin, protects coastal sage scrub, riparian habitat, freshwater marsh, and grasslands in an unusual open-space setting amid development. Once part of Rancho Lomas de Santiago, granted in 1846 to Teodosio Yorba, it later passed to James Irvine, whose tenant James Peters built a ranch house and planted the surviving eucalyptus grove. The canyon also held a golf club, reservoirs that supported agriculture, a World War II Army training area, and Boy Scout Camp Myford before the Irvine Company donated the land to Orange County in 1992. Today it is valued for trails, wildlife, and birdwatching.