1. On August 3, 1805, the Lewis and Clark Expedition passed through what is now known as Montana, becoming the first documented white explorers to explore the region. They passed through the Bitterroot Valley and encountered several Native American tribes.

2. The town of Virginia City, Montana was founded on August 3, 1863. It quickly grew into a bustling mining town, producing millions of dollars worth of gold and silver. Today, it is a popular tourist destination known for its well-preserved historic buildings.

3. On August 3, 1909, famed Western artist Charles M. Russell passed away in Great Falls, Montana. Russell is known for his depictions of the American West and its people, and his art has become an important part of Montana's cultural heritage.

4. The Montana State Capitol building in Helena was dedicated on August 3, 1912. The building, which was designed by architect Frank Mills Andrews, is an iconic landmark in Montana and houses the offices of the state's governor, lieutenant governor, and other government officials.

5. On August 3, 1985, astronaut and Montana native Loren Acton flew on the shuttle Challenger as part of the Spacelab 2 mission. Acton conducted experiments related to astrophysics and became the first scientist-astronaut from Montana to travel to space.