1. In 1804, the Lewis and Clark Expedition reached the mouth of the Kansas River, where they met with several Native American tribes. This was a significant event in the exploration of the American West.

2. In 1859, the University of Puget Sound was founded in Tacoma, Washington. It is one of the oldest private universities on the West Coast.

3. In 1890, Seattle's fire department was officially established. Prior to this, firefighting had been largely handled by volunteer companies.

4. In 1922, the town of Lowell, Washington was destroyed by a massive rockslide. The slide was caused by logging operations in the area, and it remains one of the deadliest landslides in US history.

5. In 1979, the Seattle SuperSonics won the NBA championship, defeating the Washington Bullets in five games. This was the first major professional sports championship for a Seattle team.