The Schilling Archeological District (Smithsonian trinomial 21WA1) is a prehistoric Native American archaeological site on private property on Lower Grey Cloud Island in Cottage Grove, Minnesota, United States. It consists of a habitation site and mound group with artifacts that date from the Early Woodland Period to the Late Prehistoric Period (1000 BCE–1700 CE). It was listed on the National Register of Historic Places in 1978 for having state-level significance in the theme of archaeology. It was nominated for its rare Early Woodland component, Middle Mississippian cultural influences, and potential to show climatic adaptations over time.