Before passenger train service stopped in 1959, commuter trains had been using parts of the Greenbush line for over 100 years.
Train service was first started by the South Shore Railroad which was chartered in March 1846 to build a branch off the Old Colony Railroad at Braintree.
It opened to Cohasset on January 1, 1849, running three round trips per day with Old Colony equipment.
The South Shore separated from the Old Colony in 1854.
The Old Colony-backed Duxbury and Cohasset Railroad, chartered in 1867, opened to South Duxbury in 1871 and to a junction with the Old Colony at Kingston in 1874.
After an economic collapse in the 1870s, the Old Colony acquired the South Shore in 1877 and the Duxbury and Cohasset in 1878 and combined them as the South Shore Line.

The Nantasket Beach Railroad opened in 1880 from Nantasket Junction to the Pemberton section of Hull in 1880 and joined the Old Colony in 1881.
After closing in 1886, it reopened in 1888.
A second track was added to the South Shore Line in 1890 from Braintree to Nantasket Junction to support Nantasket Beach service.

In March 1893, the Old Colony Railroad and all its trackage, including the South Shore Line and the Nantasket Beach Branch, were taken over by the New York, New Haven and Hartford Railroad.
Before passenger train service stopped in 1959, commuter trains had been using parts of the Greenbush line for over 100 years. Train service was first started by the South Shore Railroad which was chartered in March 1846 to build a branch off the Old Colony Railroad at Braintree. It opened to Cohasset on January 1, 1849, running three round trips per day with Old Colony equipment. The South Shore separated from the Old Colony in 1854. The Old Colony-backed Duxbury and Cohasset Railroad, chartered in 1867, opened to South Duxbury in 1871 and to a junction with the Old Colony at Kingston in 1874. After an economic collapse in the 1870s, the Old Colony acquired the South Shore in 1877 and the Duxbury and Cohasset in 1878 and combined them as the South Shore Line.
The Nantasket Beach Railroad opened in 1880 from Nantasket Junction to the Pemberton section of Hull in 1880 and joined the Old Colony in 1881. After closing in 1886, it reopened in 1888. A second track was added to the South Shore Line in 1890 from Braintree to Nantasket Junction to support Nantasket Beach service.
In March 1893, the Old Colony Railroad and all its trackage, including the South Shore Line and the Nantasket Beach Branch, were taken over by the New York, New Haven and Hartford Railroad.
Greenbush Line