1. In 1927, the Mount Rushmore National Memorial was dedicated on September 7th. The project had been in the works since 1925 when sculptor Gutzon Borglum was hired by the state of South Dakota to create a monument honoring American history.

2. The deadliest tornado in South Dakota history struck on September 7th, 1906, killing 11 people and injuring 70 more. The tornado touched down in the town of Watertown in the northeast part of the state.

3. The first Sioux Falls Airshow was held on September 7th, 2013, featuring performances by the United States Air Force Thunderbirds and other military and civilian aircraft.

4. On September 7th, 1936, the South Dakota State Penitentiary in Sioux Falls was the site of a major prison riot. Over 700 inmates were involved in the unrest, which was sparked by complaints about food and living conditions.

5. In 1876, the Ogallala Lakota Sioux Chief Crazy Horse was killed during a confrontation with U.S. soldiers near present-day Ekalaka, Montana. Although the event did not occur in South Dakota, Crazy Horse is an important figure in the state's history and is commemorated in several monuments and memorials throughout the region.