The proposed public bridge would be a joint project involving the U.S., Canada, Michigan and Ontario.

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The bridge was finished in 1962 as a joint operation between Canada and the United States.

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When the proposal was announced in 2010, about 500 people took part in a joint protest at the Tamar Bridge which joins Cornwall and Devon.

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The bid to have the bridge recognised was put forward by the UK government following a joint project with the Scottish Government, partnering with Network Rail, Transport Scotland and Historic Scotland.

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