The Williamson Mound Archeological District is an archaeological site in the southwestern part of the U.S. state of Ohio. Located north of Maud in Butler County, the mound appears to have been the work of peoples of the Hopewell tradition. Although a small hole was dug into the top of the Williamson Mound at some point before 1972, the mound remains in premium condition. It sits atop a ridgeline above an intermittent stream in a rural part of increasingly urbanized Butler County.