At that time, the M-29 designation was moved to the east side of the state along the current routing and farther north along part of what became US 25 and M-25.

[3] From there the route swings to the south, following the eastern shore of the lake before turning back to the east as it approaches the Harsens Island Ferry docks.

M-29 is the main thoroughfare with which to reach Harsens Island which connects to St. Clair Flats Wildlife Area and the communities of Grand Point, Maple Leaf and Sans Souci via M-154 by auto ferry.

[3] The route continues along the shoreline, until it meanders back inland a bit as it passes by the St. Clair and Belle River power plants, after which it runs close to the bank, once again, buffered by several riverbank residences.

As the route enters the city of St. Clair, it is known as River Road and Riverside Avenue as it serves as the main thoroughfare along the shore.

[3] Prior to the implementation of the U.S. Highway System, M-29 existed as a route that connected the Lansing area to Indiana via Charlotte and Marshall.

[9] Later in 1956, the Michigan State Highway Department made a few realignments in the Marine City as the route was moved to its present-day course.