Beloit to enter Wisconsin. Wisconsin In the state of Wisconsin, US 51 enters from Illinois at Beloit. US 51 splits off from I-39/I-90 in South Beloit, Illinois and continues northward through Janesville and Edgerton. In Edgerton, US 51 rejoins I-39/I-90 for before splitting off towards Stoughton and McFarland. US 51 runs almost parallel to I-39/I-90 through the eastern portion of Madison, crosses the Interstate in DeForest, and finally rejoins I-39 again at Portage. US 51 runs concurrently with I-39 until I-39's terminus in Wausau and continues on as a mixture of freeway and expressway until just north of the interchange with US 8. From there through Hazelhurst, US 51 is a two-lane road with sporadic three-lane sections (which were constructed in 2008). US 51 expands to four lanes, with a central fifth turn lane from Hazelhurst to Arbor Vitae; north of Arbor Vitae it returns to two lanes and continues to its northern end in Hurley, where it terminates at US 2. Major intersections Louisiana in LaPlace in LaPlace northeast of LaPlace. The highways travel concurrently to Hammond. in Hammond Mississippi in McComb south of Brookhaven in Crystal Springs. The highways travel concurrently to Jackson. in Jackson. The highways travel concurrently through the city. in Jackson in Winona in Batesville Tennessee in Memphis in Memphis in Memphis. US 51/US 64/US 70/US 79 travels concurrently through the city. in Memphis in Memphis in Memphis in Millington in Dyersburg. The highways travel concurrently through the city. in Dyersburg. I-69/US 51 travels concurrently to southwest of Troy. northeast of Union City. The highways travel concurrently to South Fulton. in South Fulton Kentucky in Fulton. The highways travel concurrently through the city. in Bardwell. The highways travel concurrently to Cairo, Illinois. in Wickliffe. The highways travel concurrently to Cairo, Illinois. Illinois in Cairo. The highways travel concurrently to near Dongola. in Richview in Sandoval. The highways travel concurrently through the village. in Vandalia Township. The highways travel concurrently to Vandalia. in Vandalia in Harristown in Harristown. The highways travel concurrently to Decatur. in Bloomington Township. The highways travel concurrently to northwest of Normal. in Bloomington. The highways travel concurrently to Normal. in Bloomington in Normal. I-39/US 51 travels concurrently to South Beloit. in El Paso in LaSalle in LaSalle on the Troy Grove–Ophir township line in Mendota Township on the Amboy–Franklin Grove township line in Dement Township in Rockford. The highways travel concurrently to