- Interstate 94 (I-94) is an east–west Interstate Highway connecting the Great Lakes and northern Great Plains regions of the United States. Its western terminus is just east of Billings, Montana, at a junction with I-90; its eastern terminus is in Port Huron, Michigan, where it meets with I-69 and crosses the Blue Water Bridge into Sarnia, Ontario, Canada, where the route becomes Ontario Highway 402. It thus lies along the primary overland route from Seattle (via I-90) to Toronto (via Ontario Highway 401) and is the only east–west Interstate Highway to have a direct connection to Canada.