Casas Adobes Plaza also features a historic Mediterranean observation tower. Casas Adobes is centered on the historic Casas Adobes Plaza (built in 1948). Pima County Public Library operates the Nanini Branch Library in Casas Adobes. Casas Adobes has numerous notable points of interest. KZLZ is licensed to broadcast from Casas Adobes, Arizona. The Foothills Mall is also on the northwest side in Casas Adobes. The Casas Adobes Plaza is a historical retail destination, dating back to 1948. However, the history of the Casas Adobes area predates the arrival of Sam Nanini. That same year, the residents of Casas Adobes voted to incorporate as their own city. Retaining walls were made with stones, adobes or mud and were built on the hillsides. Most of these buildings are adobes built in the mid-1800s. Livermore and Amador both helped each other build their adobes. Today, both adobes still exist and are the oldest structures in Milpitas. The adobes were laid in courses and cemented together with wet clay. Hazel Larson Archer and Ruth Brown, renovated adobes, built homes and lived in the area.