1. Formation of the State of Nevada: April 30, 1864, marks the day when Nevada officially became a state of the United States of America. As the 36th state to join the Union, Nevada played an important role in the American Civil War by supporting the Union's efforts.

2. Hoover Dam Completed: On April 30, 1936, one of the greatest engineering feats of the 20th century, the Hoover Dam, was completed. This massive concrete dam spanning the Colorado River played a crucial role in providing electricity and water to the southwestern United States.

3. First Gaming License Issued: On April 30, 1931, the Nevada State Legislature legalized gambling, making it the only state in the country to have legal gambling. On the same day, the first gaming license was issued to the Northern Club in Reno.

4. First Atomic Bomb Test: On April 30, 1951, the United States conducted its first atomic bomb test in Nevada, code-named Operation Greenhouse. The explosion was part of the country's nuclear weapons testing program, which lasted for over a decade.

5. Record Jackpot for Slot Machine: On April 30, 2006, a 25-year-old software engineer from Los Angeles won a record-breaking $39.7 million jackpot from a slot machine in the Excalibur Hotel and Casino in Las Vegas. The win was the largest ever recorded on a slot machine in Las Vegas history.