1. On April 18, 1906, the San Francisco earthquake was felt throughout Arizona. The magnitude 7.8 earthquake caused significant damage and loss of life in the Bay Area and was one of the deadliest disasters in U.S. history.

2. April 18, 1909, marked the establishment of the Grand Canyon National Monument. President Theodore Roosevelt proclaimed the land a protected area to preserve its natural beauty for future generations.

3. In 1912, Arizona became the 48th state of the Union on April 18. The state was created from the western half of the New Mexico Territory and has since been known for its desert landscapes and unique culture.

4. On April 18, 1923, the Arizona Highway Department was established, with the goal of creating a network of paved roads throughout the state. The department's efforts have played a significant role in Arizona's growth and economic development.

5. In 1981, the Papago Park Military Reservation was renamed to honor Senator Barry Goldwater, a native of Arizona and decorated war veteran. The Barry Goldwater Air Force Range covers more than 1.7 million acres in southwestern Arizona and is used for training purposes by the U.S. military.