Big Hill is one of the clearest lakes in Kansas, located in what is known as Kansas' "Little Ozarks."
A hiking trails emerges out of the Mound Valley Campground, and explores the hickory forests and large prairies in the area.
Warning: most of this area is open to hunting.
37.275009, -95.472322
http://www.tripleblaze.com/trail.php?c=3&i=6705