Oracle is a census-designated place in Pinal County, Arizona, United States. The population was 3,686 at the 2010 census.Buffalo Bill Cody owned the High Jinks Gold Mine in Oracle briefly and, in 1911, appeared as "Santa" for a group of local children. The community is the location of the Biosphere 2 experiment. Oracle was also the postal address for environmentalist author Edward Abbey, who never lived in the town but visited often. Oracle is becoming a bedroom community for Tucson, Arizona, but large-scale development is opposed by many residents.Oracle State Park is adjacent. The Arizona Trail passes through the Park and community. Oracle is the gateway to the road up the "back side" of Mount Lemmon, which starts off of American Avenue and currently offers a secondary route to the top. Prior to the construction of the Catalina Highway on the opposite side of the Santa Catalina range, the Oracle Control Road was the only road access to the mountain community of Summerhaven.