Arivaca is an unincorporated community in Pima County, Arizona. It is located 11 miles north of the Mexican border and 35 miles northwest of the port of entry at Nogales. The European-American history of the area dates back at least to 1695, although the community was not founded until 1878. Arivaca has the ZIP code 85601. The 85601 ZIP Code Tabulation Area had a population of 909 at the 2000 census.The Arivaca community lies on the north side of the Arivaca Creek valley at an elevation of 3,643 feet. The Las Guijas Mountains rise to the northwest and the foothills of the San Luis Mountains are to the south. A unit of the Buenos Aires National Wildlife Refuge occupies the Arivaca Creek valley to the southeast of the town.Arivaca Road connects with I-19 at Amado about 23 miles to the northeast and with Arizona State Route 286 some 12 miles to the west in Altar Valley.