

Access is provided to CTH-V (West North Street) via exit 126 just west of DeForest four miles (6.4 km) further north. The last two Madison area interchanges are US 51 three miles (4.8 km) northwest of the US 151 interchange and WIS 19 another one mile (1.6 km) northwest of the US 51 interchange. About two miles (3.2 km) to the north, the highway crosses US 151, which includes a south side access to High Crossing Boulevard. I-39/I-90 bypasses Madison to the east, and I-94 joins the concurrency at the eastern terminus of WIS 30, an interchange known as the Badger Interchange. It then turns gradually back to the north and meets US 12 and US 18 in Madison. The Interstate gradually turns westward around Utica to an interchange with CTH-N, providing access to Stoughton and Cottage Grove. US 51 leaves the route four miles (6.4 km) to the north and heads west through Stoughton. It is joined at exit 160 by US 51 from Edgerton and serves as the southern terminus of WIS 73. Subsequently, the highway enters Dane County as it passes west of Lake Koshkonong. The highway continues generally to the north, crossing the Rock River before an interchange with WIS 59 that provides access to Edgerton to the west and Milton to the southeast. The highway bypasses Janesville to the east, although interchanges with US 14 and WIS 26 (Milton Avenue) provide access to the town. WIS 11 leaves I-39/I-90 at exit 175, heading east. The I-39/I-90 concurrency continues to the north and is joined by WIS 11 about seven miles (11 km) north of the I-43 interchange. The last interchange serving Beloit is CTH-S (Shopiere Road) at exit 183. East of the town, the route has an interchange at exit 185 that serves as the terminus for both WIS 81, which heads westward into Beloit, and I-43, which provides access to Milwaukee. I-39 enters from Illinois along with I-90, passing under County Trunk Highway P (CTH-P, Stateline Road), and bypasses Beloit to the east. US 51 leaves I-39/I-90 at IL 75 at exit 1 in South Beloit, while I-39/I-90 continues north into Wisconsin.įor all but one mile (1.6 km) that I-39 is in Illinois, it is designated concurrently with US 51. There is a toll plaza just south of Rockton Road. While concurrent, I-39/I-90 follows I-90's exit numbering. I-39 then runs east concurrently with US 20 to where the Interstate joins the Jane Addams Memorial Tollway and I-90 near Cherry Valley.

Further north, I-39 crosses the Kishwaukee River before meeting US 20 on the southside of Rockford. I-39 intersects I-88 at exit 97 in Rochelle. North of I-80, the wind turbines of the Mendota Hills Wind Farm can be seen from milepost 72 at Mendota north to near Paw Paw. Just north of the Illinois River, I-39 runs east of the cities of LaSalle and Peru before intersecting I-80 at exit 59.

About 55 miles (89 km) north of the city, I-39 crosses the Illinois River over the Abraham Lincoln Memorial Bridge, which is 1.3 miles (2.1 km) long. From the city, I-39 runs north largely through rural areas, intersecting Illinois Route 251 (IL 251) at exit 8. I-39's southern terminus is less than one mile (1.6 km) from I-74 as I-74 runs around the city of Normal. In Illinois, I-39 begins at I-55, north of Bloomington–Normal, Illinois. Route description Illinois Īerial view of I-39 as it passes Minonk, Illinois, April 2012 From Portage northward, US 51 is cosigned with the Interstate and has exit numbers based on its mileage. At 29 miles (47 km) in length, this concurrency of three Interstates is the longest in the country. In Wisconsin, I-94 joins the pair in Madison until Portage. From Rockford, Illinois, to Portage, Wisconsin, I-39 runs concurrently with I-90. With the exception of an eight-mile (13 km) segment around Portage, Wisconsin, the Interstate shares a route with at least one other route number in I-39's entirety. In Wisconsin, I-39 has a distance of 182 miles (293 km). In Illinois, the route has a total length of 140.82 miles (226.63 km). Route 51 (US 51), which, in the early 1980s, was one of the busiest two-lane highways in the United States. I-39 runs from Normal, Illinois, at I-55 to State Trunk Highway 29 (WIS 29) in the town of Rib Mountain, Wisconsin, which is approximately six miles (9.7 km) south of Wausau. Interstate 39 ( I-39) is a highway in the Midwestern United States. WI: Rock, Dane, Columbia, Marquette, Waushara, Portage, Marathon IL: McLean, Woodford, Marshall, LaSalle, Lee, Ogle, Winnebago
