Sierra Vista is a city in Cochise County, Arizona, United States. According to 2007 Census Bureau estimates, the population of the city is 43,044.The city is part of the Sierra Vista-Douglas Micropolitan Area with an estimated population of 129,518. Fort Huachuca, a U.S. Army post, is included in City population estimates and is located in the northwest part of the city. Sierra Vista, which is Spanish for "Mountain View", is located 70 mi southeast of Tucson and serves as the main commercial, cultural, and recreational hub of Cochise County. The city is accessible via Interstate 10 and State Highway 90. The city is surrounded by the Huachuca Mountains, Dragoon Mountains, Whetstone Mountains, Mustang Mountains, and Mule Mountains and is bordered on the east by the San Pedro River.