Greenfield Twp, Wabasha County, Minnesota
Figure 1. T.H. Lewis' 1884 surveying map of the Robinson Lake Mounds superimposed on an aerial photo.
T.H. Lewis surveyed this mound group on August 11 and 27, 1884. He wrote:
"This is a group of 81 mounds, mostly small tumuli, ranged closely along the brow of the bluff, some of them in contact. Two of them are connected by a low embankment, 125 ft. long, and one of the elongated mounds tapers from a width of 27 ft. to 18 ft., being 99 ft. long. The other elongated mounds are normal as to size and position. One mound (No. 79) is entirely nondescript. It seems to have been started as a wide elongated mound, but one end flares out into three short, spreading prongs. It's form suggests nothing. It is a curious anomaly in the midst of simplicity and uniformity."
Some mounds don't fall into any of the usual categories, and are termed by researchers as "Problematic". This mound seems to belong to that category.
Figure 2. Unusual shaped mound in the Robinson Lake Mound Group.