By the end of World War I, the rapid growth of Michigan's recreation industry had created a need for a statewide parks system. In 1919 the State Park Commission was established, and D. H. Day State Park, honoring the commission's chairman, became the first park it set up. When state parks were transferred to the Conservation Department in 1921, more than twenty other sites had been acquired, most of them, like D. H. Day State Park, beautifully located on lake shores.