Many U.S. states are famous for their lakes—Minnesota has over 10,000, and Florida has thousands as well. However, Maryland is often cited as the only state in the United States without a single natural lake. Every significant body of water in Maryland that is called a 'lake' is actually a man-made reservoir created by damming rivers for water supply, flood control, or recreation. For example, Deep Creek Lake, the state’s largest, was created in the 1920s. This geological quirk is due to the state's topography and its history during the last glacial period, which did not leave behind the 'kettle' basins or glacial scours that formed natural lakes in more northern states.