1. In 1883, the first train arrived in Rapid City, South Dakota. This was a huge milestone for the city, which had been founded only a few years earlier. The arrival of the train made it much easier for residents to travel in and out of the town, and helped boost the local economy.

2. On September 5, 1910, a massive forest fire swept through the Black Hills of South Dakota. The fire burned for over a week, destroying more than 1,000 buildings and killing several people. It was one of the deadliest and most destructive fires in the state's history.

3. September 5, 1937, was the day that Mount Rushmore was dedicated. The famous national monument took nearly 14 years to complete, and it was finally opened to the public on this day. The dedication ceremony was attended by thousands of people, including several presidents.

4. In 1959, the South Dakota State Capitol building in Pierre was completed. The building had been under construction for several years, and it finally opened to the public on September 5 of that year. The capitol building remains one of the most impressive buildings in the state, and is an important symbol of South Dakota's government.

5. On September 5, 1973, the Crazy Horse Memorial was dedicated. The monument, which is still under construction, honors the Lakota warrior Crazy Horse and is meant to be a symbol of Native American culture and heritage. The dedication was attended by several Native American leaders and representatives from all over the world.