Interstate 69 (I-69) is a part of the Interstate Highway System that will eventually run from the Mexican border in Texas to the Canadian border at Port Huron, Michigan. In Michigan, it is a state trunkline highway that enters the state south of Coldwater and passes the cities of Lansing and Flint in the Lower Peninsula. A north–south freeway from the Indiana–Michigan border to the Lansing area, it changes direction to east–west after running concurrently with I-96. The freeway continues to Port Huron before terminating in the middle of the twin-span Blue Water Bridge while running concurrently with I-94 at the border. There are four related business loops for I-69 in the state, connecting the freeway to adjacent cities.

Port Huron is a city in the U.S. state of Michigan and the county seat of St. Clair County. The population was 28,983 at the 2020 census. The city is bordered on the west by Port Huron Township, but the two are administered autonomously.