1. In 1879, the first ever Wyoming state fair was held in Cheyenne on June 21st, attracting visitors from all over the state.

2. On June 21, 1904, the famous Outlaw Butch Cassidy robbed the Union Pacific train in Wilcox, Wyoming with his gang. The heist, which resulted in a $30,000 robbery, is still considered one of the most daring in the Old West.

3. In 1921, the first ever automobile race was held in Natrona County, Wyoming on June 21st. The race was sponsored by the Casper Chamber of Commerce and saw drivers from all over the state competing for a prize of $500.

4. On June 21, 1977, the Grand Teton National Park was added to the UNESCO World Heritage List, recognizing its unique natural beauty and ecological importance.

5. In 1987, June 21st was declared as "Statehood Day" by the Wyoming Legislature, commemorating the day in 1890 when Wyoming became the 44th state in the USA. The day is now celebrated with various events and activities throughout the state.