The Western Railroad was chartered February 15, 1833 and incorporated March 15, 1833 to connect the B&W to the Hudson and Berkshire Railroad at the New York state line. Construction began in 1837, and the Eastern Division to the Connecticut River in Springfield opened on October 1, 1839. The summit of Charlton Hill drainage divide between the Atlantic coast and the Connecticut River is a rock cut 57 mi (92 km) west of Boston. The Western Division, through the Berkshire Hills, opened in sections from both ends from the state line to Pittsfield May 4, 1841, West Springfield to Chester May 24, 1841, Springfield to West Springfield (across the Connecticut River) July 4, 1841, Pittsfield to "Summit" August 9, 1841, and Chester to Summit September 13, 1841. The summit through the Berkshires is known as Washington Hill. Eastbound trains climb 6 mi (9.7 km) of 1.4% grade while westbound trains climb 10 mi (16 km) of slightly steeper grade to reach the 4 mi (6.4 km) of fairly level track across the drainage divide between the Connecticut and Hudson Rivers. On October 4, 1841 the first train ran along the full route. The only true tunnel on the B&A is State Line Tunnel in Canaan, New York, about 2 mi (3.2 km) west of the Massachusetts state line. The original bore was augmented by an improved-alignment second tunnel in 1912, and the original bore was abandoned in the late 20th century.