1) On October 12, 1492, Christopher Columbus first made contact with the New World, but it wasn't until centuries later that South Dakota played a role in honoring his legacy. In 1958, the city of Rapid City dedicated a statue of Columbus in Memorial Park, which still stands today.

2) On October 12, 1868, the first train to cross the Missouri River into Dakota Territory arrived in Yankton. This marked a major milestone in the development of transportation in the region, and helped to spur growth and economic development.

3) On October 12, 1961, the U.S. government announced plans to build a missile installation near the town of Interior, near the Badlands. The installation, known as the Minuteman Complex, would eventually become one of the largest nuclear missile sites in the country.

4) In 1993, October 12 was officially recognized as Native American Day in South Dakota, in honor of the state's many indigenous peoples and their contributions to the region's history and culture.

5) On October 12, 2009, the town of Keystone was officially designated as a National Heritage Area by the U.S. government. This designation recognizes the town's important role in the development of the Black Hills region, as well as its rich cultural and historical significance.