The lines of the Canadian Pacific Railway operated in the State of Maine were set up as a separate company to comply with Interstate Commerce Commission regulations and were considered a Class I U.S. railroad (in 1950, railroads with operating revenues over $1 million). The company operated 234 miles in Maine. Its primary route formed the Canadian Pacific east–west main line between Montreal, Quebec and Saint John, New Brunswick. From 1889 to 1974 part of the through route consisted of trackage rights over the Maine Central Railroad between Mattawamkeag, Maine and Vanceboro, Maine.