United States map showing the area included in the Louisiana Purchase.

October 20, 1803

The U.S. Senate approves the Louisiana Purchase that adds more than 800,000 acres of land – including what would become Missouri – to more than double the size of the United States.

July 17, 1804

The Corps of Discovery spent this day resting. This was the last full day they would have in the area which was to become Missouri.