King's Highway 402, commonly referred to as Highway 402 and historically as the Blue Water Bridge Approach, is a 400-series highway in the Canadian province of Ontario that connects the Blue Water Bridge international crossing near Sarnia to Highway 401 in London. It is one of two vital trade links between Ontario and the Midwestern United States. The controlled access freeway is four-laned for nearly its entire length, except on the approach to the Blue Water Bridge, where it widens.

Although Highway 402 was one of the original 400-series highways when it was designated in 1953, it was not completed until 1982, when the final link between Highway 81 and Highway 2 opened to traffic. The freeway originally did not exit the Sarnia city limits, and merged into Highway 7 near the present Highway 40 interchange. In 1972, construction began to extend Highway 402 between Sarnia and London; this work was carried out over a decade. The removal of an intersection at Front Street in Sarnia made the entire route a controlled-access highway.

Motorists crossing into Michigan at the western end have direct access to Interstate 69 (I-69) and Interstate 94 (I-94) into Port Huron; motorists crossing onto the Canadian side from the east end of I-69 and I-94 have access to Toronto via Highway 401, and onwards to Montreal via A-20 in Quebec. The only town along Highway 402 between Sarnia and London is Strathroy.

en.wikipedia.org/wiki/Ontario_Highway_402