Wyoming from the west US 14 begins at the east entrance to
Yellowstone National Park, along with US 16 and the eastern segment of US 20. It travels through
Shoshone National Forest to
Cody, where
US 14A splits off to the north. Both routes traverse the dry
Bighorn Basin, followed by a steep ascent up the
Bighorn Mountains and through the
Bighorn National Forest, where they rejoin at Burgess Junction. The highway descends the eastern slope of the Bighorn Mountains between Burgess Junction and
Dayton. US 14 briefly follows I-90 south from
Ranchester to
Sheridan. The highway turns east and then south to again join I-90 near
Gillette. It splits off for a short time to Carlile, then rejoins I-90 which it follows to the state line.
South Dakota The South Dakota section of US 14 enters the state from
Wyoming concurrent with I-90. It passes through
Spearfish,
Sturgis,
Rapid City, and
Wall, before leaving I-90. US 14 then passes through
Philip,
Midland,
Pierre,
Highmore,
Miller,
Wolsey,
Huron,
De Smet,
Arlington,
Volga, South Dakota, and
Brookings, then leaving the state at the
Minnesota state line. US 14A winds through the northern part of the scenic
Black Hills taking travelers from Sturgis to Spearfish. The Laura Ingalls Wilder Historic Highway incorporates US 14 from De Smet in the west to
Rochester, Minnesota, in the east. US 14 and US 83 serve Pierre, one of only four state capitals not on the
Interstate Highway System. The South Dakota section of US 14 is legally defined at South Dakota Codified Laws § 31-4-134.
Minnesota , and
State Trunk Highway 16 across the Mississippi River between La Crescent, Minnesota, and La Crosse, Wisconsin. This is the river's West Channel. US 14 enters the state from South Dakota west of
Lake Benton. It goes east through several small towns such as
Balaton,
Tracy,
Revere,
Lamberton,
Sanborn, and
Sleepy Eye, on a two-lane road until
New Ulm, where it is briefly a
divided highway. From New Ulm to
Mankato, the highway lies north of the
Minnesota River. Shortly before coming to the
Mankato – North Mankato metropolitan area, US 14 becomes a freeway
bypass, which becomes an expressway east of Mankato. This section is part of the
Laura Ingalls Wilder Historic Highway as it passes through
Walnut Grove. It currently continues east south of
Waseca, and, at
Owatonna, it crosses
I-35 at a
cloverleaf interchange. It then heads east toward
Rochester, with an expressway segment beginning at
Minnesota State Highway 56 (MN 56) and continuing east into Rochester. Once it enters Rochester, it has a concurrency with
US 52. After the concurrency, it continues through Rochester as a divided highway. After Rochester, the highway parallels
I-90 until
Winona, where US 14 gets picked up by
US 61. The two highways run concurrently the rest of the way in Minnesota and cross the
Mississippi River at
La Crescent over the
La Crosse West Channel Bridge. US 14 was extended to a full,
limited-access freeway from approximately west of Janesville to I-35 at Owatonna. Most of the new route is located south of the existing alignment so as to avoid overlapping I-35. The expansion was opened to traffic on August 31, 2012, creating a continuous four-lane route from
North Mankato to Owatonna. The section from Waseca to
Janesville has yet to be upgraded to freeway standards; it currently exists as an expressway. The four-lane expressway was extended from North Mankato to
Nicollet including a southwest bypass of Nicollet and an
interchange for
MN 111 in 2016. Between Owatonna and Dodge Center, US 14 was upgraded to a freeway in 2021. The new freeway opened to traffic in late 2021. The segment from Nicollet to New Ulm has been upgraded to a four-lane expressway including a bypass of
Courtland. Construction began in 2022 and was completed in November of 2023 after a month long delay due to concrete paving delays. US 14 is being planned to be upgraded to a freeway between
Byron and Rochester with three new interchanges planned. An interim safety project will construct two reduced conflict
intersections in 2022. The Minnesota section of US 14 is defined as part of
Constitutional Route 7 and Trunk Highways 121 and 122 in the
Minnesota Statutes. {{wide image|La Crosse area view over I-90.jpg|600px|U.S. Route 14/
61 junction with
I-90|75%|center
Wisconsin US 14 enters the state of Wisconsin along with
US 61 across the
Mississippi River into
La Crosse. Running through rural southern Wisconsin, it then meets with
US 12 outside of
Madison. Following the Beltline Highway around Madison, it meets
US 18 and
US 151, before turning south, passing through some southern Madison suburbs,
Oregon, and
Evansville before approaching
Janesville. Bypassing Janesville to the north, US 14 intersects
US 51, as well as
I-90 and
I-39. It then travels southeast, past
I-43, to the village square of
Walworth. US 14 then turns south and exits into
Illinois at
Big Foot Prairie.
Illinois In the state of Illinois, US 14 runs southeast from north of
Harvard to
Chicago via
Woodstock and the northwest suburbs. Southeast of
Illinois Route 47 (IL 47), US 14 has four lanes, and, at times, it is a high-speed divided highway. Continuing southeastward from just after the overpass above
IL 31, US 14 passes beneath and then closely parallels the tracks of the
Union Pacific Railroad's
Harvard Subdivision. Through the northwest suburbs of Chicago, this route is commonly referred to as "Northwest Highway" and is a very busy thoroughfare. East of
Des Plaines, US 14 becomes
Dempster Street until its intersection with Waukegan Road. From here, US 14 follows Waukegan Road, Caldwell Avenue, Peterson Avenue, and
Ridge Avenue to its eastern end, at the corner of
Broadway and
US 41 (
Foster Avenue). At an earlier point, US 14 extended south on Lake Shore Drive onto Michigan Avenue. ==History==