[1] The company's initial purpose was to establish a new east−west link between Boston, Massachusetts, and points west, via the Hoosac Tunnel, which had been completed in 1875.

The Boston, Hoosac Tunnel and Western Railway would build between Mechanicville, New York and the Massachusetts/Vermont state line, where it would connect with the Massachusetts-owned Troy and Greenfield Railroad.

In the west, the Delaware and Hudson Railway (D&H) would build between Schenectady, New York, and Mechanicville.

[6] The D&H completed the new line between Mechanicville and Schenectady in December 1881, eliminating the need to run via Ballston Spa, New York.

[3] A similar arrangement was made with the D&H for the parallel lines between Mechanicville and "Crescent", in the direction of Schenectady.