1. In 1934, the construction of the Hoover Dam was completed. The dam spans the Colorado River between Arizona and Nevada, providing hydroelectric power and flood control for the region.

2. On May 28, 1958, the US Air Force launched the first successful test of its new intercontinental ballistic missile, the Atlas. The missile was developed in response to the growing threat of nuclear war during the Cold War.

3. In 1987, Arizona governor Evan Mecham was impeached by the state legislature for alleged misconduct in office. Mecham was the first governor in US history to be impeached and removed from office by a state legislature.

4. The Phoenix Suns basketball team made their first NBA Finals appearance on May 28, 1993. The Suns were led by league MVP Charles Barkley, but ultimately lost the championship to Michael Jordan's Chicago Bulls in a six-game series.

5. On May 28, 2012, the Wallow Fire ignited in eastern Arizona, eventually burning over 500,000 acres and becoming the largest wildfire in state history. The fire destroyed dozens of homes and forced thousands of people to evacuate their homes.