1. The deadliest blizzard in South Dakota's history occurred on October 17, 1880. Known as the "Schoolchildren's Blizzard," it resulted in the deaths of more than 200 people, many of whom were children caught in the storm on their way home from school.

2. On October 17, 1931, the state's first commercial airport opened in Sioux Falls. The airport was initially called the Sioux Falls Municipal Airport and has since expanded to become the Sioux Falls Regional Airport.

3. The Oahe Dam, one of the largest dams in the United States, was dedicated on October 17, 1962. It is located on the Missouri River near Pierre and provides hydroelectric power, flood control, and recreational opportunities for South Dakotans.

4. On October 17, 1973, President Richard Nixon signed into law the Trans-Alaska Pipeline Authorization Act, which allowed for the construction of the Trans-Alaska Pipeline System that transports crude oil from the North Slope of Alaska to the port of Valdez. South Dakota played a role in the construction of the pipeline by providing equipment and labor for the project.

5. The South Dakota State Historical Society was established on October 17, 1898, with the goal of "collecting and preserving the records of the past of this State, and of such of its leading citizens as may have been identified with its growth and development." Today, the historical society operates the South Dakota State Archives and the South Dakota State Museum, among other programs and initiatives.