1. On April 30, 1937, the Hoover Dam was officially dedicated in a ceremony attended by President Franklin D. Roosevelt. The dam, located on the Arizona-Nevada border, was a major engineering feat that provided flood control, irrigation, and hydroelectric power to the southwestern United States.

2. April 30, 1864, marks the day that the Arizona Territory was officially created by an act of Congress. This paved the way for the eventual statehood of Arizona on February 14, 1912.

3. In 1993, on April 30, the Phoenix Suns set an NBA record for the most three-point field goals made in a playoff game. They sank 22 three-pointers in a game against the Seattle SuperSonics, ultimately winning 153-126.

4. April 30, 1906, saw the founding of the Arizona-Sonora Desert Museum, located outside of Tucson. This unique attraction combines a zoo, botanical garden, and natural history museum to showcase the ecosystems and wildlife of the Sonoran Desert.

5. On April 30, 1993, the Grand Canyon National Park celebrated its centennial anniversary. The park, located in northern Arizona, is one of the most popular tourist destinations in the United States and a UNESCO World Heritage Site.