Tucson, Arizona is 5.3 times larger than Simi Valley, California.
Area: 112 km2 calculated
Simi Valley is a city located in the valley of the same name, Simi Valley, in the southeast corner of Ventura County, California, United States. Situated 30 miles from Downtown Los Angeles, Simi Valley is part of the Greater Los Angeles Area. Wikipedia
Area: 590 km2 calculated
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