M-29 is a state trunkline highway in the US state of Michigan that runs in a south–north direction from Chesterfield Township to Marysville. It generally runs along the shore of Lake St. Clair and the St. Clair River.

Marysville is a city in St. Clair County of the U.S. state of Michigan. The population was 9,959 at the 2010 census. The municipality was founded in 1919, first as a village, then became a city in 1924.