text: m - 239 ( michigan highway ) m - 239 is a north – south state trunkline highway in berrien county in the extreme southwestern corner of the us state of michigan connecting state road 39 ( sr 39 ) in indiana to interstate 94 ( i - 94 ) . the highway was designated in 1963 , and it provided the only connection from the southern end of i - 94 into indiana until 1972 . route description as sr 39 crosses into michigan it becomes m - 239 . as soon as it crosses the border , the road curves around to the northwest where it continues through a generally rural area . the trunkline intersects wilson road and passes next to a commercial development . after a little over a mile ( 1 . 8 km ) , the road comes to its northern terminus at an interchange with i - 94 at exit 1 . while m - 239 officially ends at the interchange , the roadway , known as harbor country drive , continues on to the northwest where it heads into new buffalo . like other state highways in michigan , m - 239 is maintained by the michigan department of transportation ( mdot ) . in 2011 , the department 's traffic surveys showed that on average , 6 , 231 vehicles used the highway daily . no section of m - 239 is listed on the national highway system , a network of roads important to the country 's economy , defense , and mobility . history m - 239 always ended at i - 94 , even though harbor country drive continues into new buffalo . before completion of the indiana portion of i - 94 , the freeway ended at the present exit 1 . a 1 . 1 - mile - long ( 1 . 8 km ) stretch of laporte road was designated as m - 239 in 1963 to carry traffic to sr 39 , which connects to the indiana toll road . until 1972 , when indiana constructed their section of i - 94 , m - 239 and sr 39 were the only connection from the southern end of i - 94 in michigan across the state line . major intersections the entire highway is in new buffalo township , berrien county .