I-94 begins at Billings and travels northeastward towards Glendive before exiting the state to the east.
The route enters at Beach, passes through some beautiful scenery in the Badlands near Medora (near the Theodore Roosevelt National Park (South Unit)). A public rest area about seven miles east of Medora provides a scenic view and the Painted Canyon Trail that provides the opportunity to hike through some of the scenery. I-94 then travels east past Bismarck on the way to Fargo where it leaves the state and crosses into Minnesota.
I-94 travels in a northwest-southeast trajectory passing Moorhead and St Cloud prior to traveling through the Twin Cities and heading east out of the state. Leaving Fargo, ND and entering Moorhead, MN, I-94 crosses the Red River. In Minneapolis it crosses the Mississippi River, and leaving Minnesota between Lakeland, MN and Hudson, WI, I-94 crosses the St. Croix River. Between northbound I-35W and MN-280 in the Twin Cities, the highway is not up to interstate standards because the Minnesota Department of Transportation (Mn/DOT) added a temporary extra lane to help relieve traffic congestion caused by the collapse of the I-35W Mississippi River bridge.
Interstate 94 enters Wisconsin east of the Twin Cities at the town of Hudson. It passes Eau Claire before turning southeastward and joining with Interstate 90 in Tomah and Interstate 39 in Portage. I-94 branches off eastward in Madison and travels east to Milwaukee before turning south and heading to Chicago, entering Illinois at Pleasant Prairie.
In the state of Illinois, I-94 runs south from Wisconsin to Indiana via downtown Chicago. It is tolled on the Tri-State Tollway to the I-94/I-294 split; it then runs east to the Skokie Highway, where it turns south through the city of Chicago. At Interstate 80, I-94 runs east to Indiana on the Kingery Expressway.
In the state of Indiana, I-94 runs east from Illinois concurrent with I-80. It crosses Interstate 90 (Indiana Toll Road), where I-80 joins I-90 east towards Ohio. I-94 continues northeast, paralleling the Lake Michigan shoreline into Michigan.