The Boston and Worcester Railroad was chartered June 23, 1831 and construction began in August 1832. The line opened in sections: to West Newton on April 16, 1834; to Wellesley on July 3; to Ashland on September 20; to Westborough in November 1834; and the full length to Worcester on July 4, 1835. The original single-track line was doubled-tracked from Boston to Framingham in 1839, and on to Worcester by 1843. In 1843 the B&W introduced season passes to West Newton for $60, effectively introducing the concept of commuter rail.
B&W was merged into the Boston and Albany Railroad in either September of 1867 or December of 1870.