1. On May 20, 1873, the famous explorer and geologist Ferdinand Vandeveer Hayden arrived in Montana to begin his exploration of Yellowstone National Park. His detailed descriptions and stunning photographs of the park played a crucial role in convincing Congress to establish Yellowstone as the world's first national park.

2. In 1964, a massive earthquake struck southwestern Montana on May 20, registering 7.1 on the Richter scale. The quake caused extensive damage to buildings in the towns of Dillon and Virginia City, but miraculously no one was killed.

3. On May 20, 1911, the town of Wolf Point in northeastern Montana was officially incorporated. Wolf Point is the largest town on the Fort Peck Indian Reservation, and its residents have a proud history of participating in Native American cultural traditions.

4. In 1927, Charles Lindbergh made a historic flight over Montana on May 20 as part of his solo transatlantic journey. He flew his iconic plane, the Spirit of St. Louis, over the mountains and plains of Montana, including a breathtaking sunrise over the high peaks of the Rocky Mountains.

5. May 20, 1908 marks the birth date of Montana historian K. Ross Toole, who authored numerous books about the state's history and culture, including "Montana: An Uncommon Land" and "The Western Odyssey of John Simpson Smith." Toole was also an advocate for Native American rights and championed the preservation of Montana's unique heritage.