Santa Cruz County, 57 miles south of Tucson and 12 miles north of Mexican. The community's 39,000 acres roll gently down from the Santa Rita Mountains through the San Cayetano Foothills westward to the Santa Cruz River. Arizona Rio Rico is a planned community located in Santa Cruz County, 57 miles south of Tucson and 12 miles north of Mexican. The community's 39,000 acres roll gently down from the Santa Rita Mountains through the San Cayetano Foothills westward to the Santa Cruz River.