An Absolute Michigan feature via Michigan History Magazine on the opening of the Mackinac Bridge on November 1, 1957 says (in part):
With the bridge ready for traffic, but fearing inclement autumn weather at the Straits, officials decided to have an official “opening” on November 1, 1957, but an official “dedication” in late June of the following year.
Amazingly, the weather on the first day of November (preceded by two days of rain and fog) was sunny and pleasant. However, the weather in late June was so cold and wet (with six-foot waves on the Straits) that some of the events were shortened or canceled altogether. According to one observer, it “was a bleak, gray day, more like March than June, and the only parader who looked happy was a snow queen from Cadillac, who rode on an ice throne float, throwing snowballs made of popcorn.”
…On November 1, after paying the $3.25 toll (taken symbolically by former U.S. Senator Prentiss Brown, who chaired the Mackinac Bridge Authority), Governor G. Mennen Williams crossed the bridge (driven in a car by Mrs. Williams because the governor had forgotten his driver’s license). Then, according to United Press International correspondent Thomas Farrell, cars lined up for one mile on both sides of the Straits “swarmed” on to a bridge whose size “staggers the imagination.”
In his opening day remarks, Governor Williams predicted that the bridge would add $100 million annually to the state’s tourist trade. He continued, “Michigan at last is to be one state, geographically, economically and culturally, as well as politically.”
I think we can probably agree that it’s had a tremendous impact on Michigan! About this photo with a unique view of the festivities, Dave writes:
A friend found this large format color slide earlier this year and I scanned it at high resolution. It shows Governor G. Mennen “Soapy” Williams at the tollbooths on the St. Ignace end of the Mackinac Bridge on the day it opened, November 1, 1957. I have seen many photos of this day, but never one quite like this.