Casa Grande is located near the point where the I-10 and I-8 separate with the I-8 heading west to Gila Bend and Yuma. Casa Grande is the largest city in Pinal County and is named for the Hohokam ruins at Casa Grande Ruins National Monument (which is actually in Coolidge). Casa Grande was founded during the Arizona mining boom in 1879. When the railroad came to town, Casa Grande was named "Terminus," because that railroad terminated here. However, the city was incorporated as Casa Grande in 1915.

Casa Grande may have been founded during the mining heydays but for many years, the local economy was based on cotton and dairy farms. Recently, though, the city has become more of a bedroom community with a large number of residents commuting to jobs in Phoenix or Tucson daily. Casa Grande is also beginning to attract some manufacturing facilities and retail outlets, including an outlet mall on the south side of town. Just west of Casa Grande proper is the Francisco Grande Hotel and Golf Resort where the San Francisco Giants used to do their spring training.