Lake Afton is a man-made reservoir in western Sedgwick County, Kansas, created by a dam project begun on December 29, 1939, and built from 1939 to 1941 by Works Progress Administration laborers, tying it to the New Deal era of public works. Though completed earlier, the lake opened to the public in 1945. Set within a 720-acre county park, it later gained additional public uses beyond recreation, including the Sedgwick County Boys Detention Home in 1960 and the Lake Afton Public Observatory in the late 1970s. It remains a notable rural open-space destination centered on one reservoir landscape.