1. On December 12, 1914, the first football game was played at the University of Arizona's new football stadium. The game was against the University of Utah, and the stadium was later named Arizona Stadium.

2. In 1962, the Hoover Dam bypass project was approved by Congress. The bypass was built to alleviate traffic on the dam and improve safety on the highway. It was completed in 2010 and is now known as the Mike O'Callaghan–Pat Tillman Memorial Bridge.

3. On December 12, 1987, the first section of the Light Rail Transit system began construction in Phoenix. The system has since grown to include 28 miles of track and 50 stations throughout the Phoenix metropolitan area.

4. December 12, 2011, marked the one-year anniversary of the shooting in Tucson in which Congresswoman Gabrielle Giffords was seriously injured. The city held vigils and memorials to remember the victims on this day.

5. In 1989, Arizona became the first state to pass a law allowing charter schools. The schools are publicly funded but operate independently of the traditional public school system, allowing for more flexibility in curriculum and teaching methods. Today, there are over 500 charter schools in Arizona.