M.27 a.k.a. M-27 is a north–south state trunkline highway in the extreme north of the Lower Peninsula of the US state of Michigan. The route runs between Interstate 75 just north of Indian River and Cheboygan, where it meets US Highway 23 near Lake Huron. It remains as a relic of the old US 27 which disappeared north of Grayling after being supplanted by I-75, which lies close to old US 27 between Grayling and Indian River.
M.27: The 75 mm M.27 was a Norwegian mountain gun used in World War II. Twenty-four of these guns were designed and built by Kongsberg Kanonfabrik to supplement the old 75mm Ehrhardt M.11 guns.