1. In 1934, the Hoover Dam was officially dedicated by President Franklin D. Roosevelt. The dam, located on the border between Arizona and Nevada, provides hydroelectric power and water storage for the surrounding region.

2. On October 30, 1981, the Arizona Cardinals played their first game at Sun Devil Stadium in Tempe, Arizona. The Cardinals relocated from St. Louis to Arizona in 1988 and currently play at State Farm Stadium in Glendale.

3. In 1870, the First Arizona Mining District was established in Mohave County. This district was instrumental in the development of Arizona's mining industry, which produced copper, gold, silver, and other minerals that continue to fuel the state's economy to this day.

4. In 1938, the Arizona State Fairgrounds opened in Phoenix, Arizona. The fairgrounds host the annual Arizona State Fair and a variety of other events throughout the year, including concerts, festivals, and sporting events.

5. On October 30, 1986, the Maricopa County Jail in Phoenix, Arizona, experienced one of the largest inmate riots in U.S. history. The riot, which began as a protest against overcrowding and poor conditions, resulted in extensive damage to the facility and the injury of several inmates and correctional officers.