served by US 25 between Detroit and Port Huron. The first span of the Blue Water Bridge opened between Port Huron and Point Edward, Ontario, in 1938. Early conversions to freeways The first segments of upgraded highways along the future route of I-94 were added during World War II. Construction on the Willow Run Expressway started in 1941 before the US entered the war. It was opened on September 12, 1942, to provide improved access to Ford Motor Company's Willow Run bomber plants. The highway was given the M-112 designation at the time. The expressway was extended eastward as the Detroit Industrial Expressway into Detroit; the first section opened in 1943 and the remainder was completed in March 1945. Land acquisition for the Edsel Ford Freeway started in 1945. Originally referred to as the Crosstown Freeway, the freeway became known as the Edsel Ford Freeway following an April 1946 petition. The interchange between the Lodge Freeway and the Edsel Ford Freeway was built in 1953 as the first full freeway-to-freeway interchange in the US. In mid-1956, the M-112 designation was decommissioned and replaced by a rerouted US 12. During the mid-1950s, the Detroit Streets and Rails campaign proposed a high-speed rail line in the median of the Willow Run, Detroit Industrial and Edsel Ford freeways; instead of building the rail line, special boarding stations adjacent to dedicated bus lanes in the interchanges along the highway were used. In other parts of the state, other segments of highway were built to bypass the cities along the future I-94 corridor. In 1940, a southern bypass of Battle Creek opened along Columbia Avenue, and the former routing through downtown on Michigan Avenue became Business US 12 (Bus. US 12). In late 1951 or early 1952, a northerly bypass of Jackson opened, and the former route through downtown on Michigan Avenue became another Bus. US 12. By the next year, the western half of the Jackson bypass opened, including a bypass of Parma. In 1954, a new bypass of Kalamazoo and Galesburg opened; US 12 was rerouted to follow the new highway while M-96 replaced part of the old route and US 12A in the area. The first planning maps from 1947 for what later became the Interstate Highway System included a highway along I-94's route in Michigan. This highway was included on the 1955 plan for the "National System of Interstate and Defense