Winona, Minnesota
Figure 1. T.H. Lewis' 1884 surveying map of the mounds west of Winona superimposed on an aerial photo.
T.H. Lewis surveyed this site on July 30, 1884. Lewis wrote:
"This group embraces 14 mounds, one of which No. 3 is broad elongated, almost circular, having dimensions 61 ft. by 45 ft. by 3 ft. No 9 is a rude effigy without head, somewhat resembling the human figure and Nos 1, 2, 6 and 7 have been somewhat excavated. The tumuli average large for size, the largest (No. 11) being 60 ft. by 5 ft. There were formerly several mounds on the south side of the public road. The top of No. 11 is 12 ft. above the marsh."
Some bird effigy mounds in Wisconsin have forked tails, so it's not clear what this was meant to represent. It's also not clear how its orientation relates to any nearby waterway.
Figure 2.The "Rude Effigy" mound measured about 75 feet in length.