Huntsville is a city located primarily in Madison County in the central part of the far northern region of the State of Alabama. Huntsville is the county seat of Madison County. The city extends west into neighboring Limestone County. Huntsville's population was 180,105 as of the 2010 census. Wikipedia

Tucson is a city in and the county seat of Pima County, Arizona, United States, and home to the University of Arizona. The 2010 United States Census puts the city's population at 520,116, while the 2013 estimated population of the entire Tucson metropolitan area was 996,544. Wikipedia