Atlantic and St. Lawrence Railroad

Canadian railroad

Also known as: St. Lawrence and Atlantic Railroad

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June 18, 2026

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The Atlantic and St. Lawrence Railroad was an early Canadian railroad, incorporated in 1852-53. Its primary goal was to connect the Province of Canada (modern-day Ontario and Quebec) with Portland, Maine, on the U.S. seacoast. By completing its final link between Montreal and Portland in July 1853, it became North America's first international railroad.1

The railroad adopted a gauge of 5 feet 6 inches (1,676 mm) at the behest of its Maine promoters, which became the first widely adopted Canadian gauge. This gauge was later narrowed to the standard gauge as international boundary crossings increased. The Grand Trunk Railway eventually acquired and extended this line, constructing a significant portion of Quebec and Ontario's main railway system.21

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…it was known as the Atlantic and St. Lawrence Railroad in the three northern New England states and the St. Lawrence and Atlantic in Quebec. At the behest of the Maine promoters of this line, a gauge of 5 feet 6 inches (1,676 mm) was adopted to exclude Boston and…
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…it was known as the Atlantic and St. Lawrence Railroad in the three northern New England states and the St. Lawrence and Atlantic in Quebec. At the behest of the Maine promoters of this line, a gauge of 5 feet 6 inches (1,676 mm) was adopted to exclude Boston and…
Read More