The two Mckinstry mounds are located on the American side of the Rainy River at the mouth of the Littlefork River. The site is about five miles east of the Grand Mound (Smith site), which is also part of the Laurel culture. The most thorough excavation of the McKinstry mounds was done by Lloyd A. Wilford with a WPA crew in 1939, and Mound 1 was revisited by James B. Stoltman in 1970.
Wilford concluded that the McKinstry site was occupied by two Aspects; The Rainy River and Headwaters Lake Aspects.
The Rainy River or Laurel Aspect was evidenced by socketed antler points and pointed beaver teeth. The single burials and Laurel pottery are also characteristic of the Rainy River aspect.
The Headwaters Lake Aspect was indicated by the presence of Blackduck pottery sherds. Most of the sherds were distributed in the higher levels of the stratification, so it was concluded that they occupied the site at a later time. Also, it followed that all the group burials were made by the Headwaters Lakes people.
Mound 1 components were primarily of the Rainy River Aspect and it is thought that the area mound 1 covers was once a living area. Firehearths and village debris was found in the topsoil beneath the mound. The debris included broken artifacts, potsherds, flint chips, and bones of mammals, birds and fish (mostly sturgeon). No skeletons were found beneath the mound, but human bone fragments were recovered
Mound 2 contained burials of a wide variety including primary and secondary burial, disarticulation, and cremation in place. Some eye sockets had been filled with clay and appeared to have been fire hardened. Red ochre was found with several skeletons, and small mortuary pots, copper ornaments were associated with the burials. One third of the potsherds were of the Blackduck type, the balance being of the Laurel type.
Distinct similarities appeared between these mounds and the mounds at the Smith and Pike bay sites, all within the Laurel Aspect.
Wilford, Lloyd A. The McKinstry Merinds of the Rainy River Aspects, Minnesota Archaeologist, Vol. 18 No. 2, 1952
Stoltman, James B., An Examination of Within-laurel cultural Variability in Northern Minnesota. Contained in Aspects of Upper Great Lakes Anthropology, Johnson, Elden, Editor, Papers in honor of Lloyd A. Wilford, Minnesota Historical Society, St. Paul, 1974.