The Montreal, Portland and Boston Railway was an international railroad located in northern Vermont and southern Quebec. In 1871 it was formed as the Montreal, Chambly, and Sorel Railway Company, a company which constructed their line from Saint Lambert opposite Montreal to Chambly. Upon merging with the Missisquoi Junction Railway Company in 1874, it retained its name.[1] In 1875 it became the Montreal, Portland and Boston Railway Company,[2] with the intent of creating a new Montreal to Boston route via the Portland and Ogdensburg Railroad. To achieve this, the MP&B extended their line from Chambly to Frelighsburg, Quebec, and to Sheldon, Vermont in 1881; at Sheldon Junction it connected with the P&O.
The failure of the P&O also marked the downfall of the MP&B, and in 1883 traffic had declined enough that the tracks south of Farnham were abandoned and removed, only a year after the line's completion. In 1886 and 1888, the company and its former management were involved in litigation in Montreal concerning debts and possible fraud.[3] The line was sold to the Central Vermont Railway and reorganized as the Montreal and Province Line Railway in 1898, which restored the line north of Frelighsburgh in 1901.