Arivaca is an unincorporated community in Pima County, Arizona, United States. It is located 11 miles (18 km) north of the Mexican border and 35 miles (56 km) 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.