Coba jelasin History dari MBTA Commuter Rail dong

Eight intercity mainlines radiating from Boston opened between 1834 and 1855: the Boston and Worcester Railroad (B&W) in 1834–35, Boston and Providence Railroad (B&P) in 1834–35, Boston and Lowell Railroad (B&L) in 1835, Eastern Railroad in 1838–1840, Fitchburg Railroad in 1843–45, Boston and Maine Railroad (B&M) in 1845, Old Colony Railroad and Fall River Railroad in 1845–46, and Norfolk County Railroad in 1849–55. Commuter rail service allowing suburban residents to work in Boston began with the B&W in 1834; by the 1860s, commuting was possible on the eight mainlines and a number of branch lines. Mergers prior to the 1880s were primarily acquisitions of branch lines and consolidations with connecting lines: the B&A merged with the Western Railroad in 1874 to become the Boston and Albany Railroad (B&A), the Fall River Railroad and several other lines merged into the Old Colony Railroad, and the Norfolk County Railroad eventually became part of the New York and New England Railroad (NY&NE). The narrow gauge Boston, Revere Beach and Lynn Railroad (BRB&L) opened in 1875, competing with the inner portion of the Eastern Railroad. Unlike the other lines, it never built rails into downtown Boston, and instead relied on a ferry connection from East Boston.

The B&M obtained control of the Eastern in 1883, the B&L in 1887, and the Fitchburg in 1900, giving it a near-monopoly on rail service north of Boston. North Union Station was built in 1893 to provide a union station for northside service; it was replaced by North Station in 1928. The Old Colony obtained control of the B&P in 1888; the New York, New Haven and Hartford Railroad acquired the Old Colony in 1893 to obtain access to Boston. The New Haven also acquired the New England Railroad (successor to the NY&NE) in 1898. South Station opened in 1899 as a union station for the southside lines (New Haven and B&A). The New York Central and Hudson River Railroad – which later became the New York Central) (NYC) – leased the B&A in 1900; this brought all Boston commuter service save the BRB&L under the control of three large multi-state railroads.

The three railroads all planned electrification of some suburban lines in the early 20th century. The New Haven tested electrification on small parts of the Old Colony system, but never followed through on its plans to electrify South Station and the inner section of the ex-B&P. Despite a study to electrify the mainline to  plus the Highland branch, the NYC only electrified the short Lower Falls Branch. Quadruple-tracking and electrification of part of the ex-Eastern Railroad was planned by the B&M around 1910 when it was briefly under control of the New Haven, but this fell through when they separated. Service levels on the three major railroads peaked around 1910 and began to decline from streetcar and later auto competition in the 1910s. The independent BRB&L electrified its mainline and single branch line in 1928 and increased service to near-rapid transit levels. Two Old Colony branches were converted to an extension of Boston Elevated Railway (BERy) rapid transit in the 1920s.

Service levels declined more significantly during the 1930s; the 88 stations case resulted in the New Haven closing dozens of suburban stations and several lines in 1938. The BRB&L ceased all operations in 1940. Ridership increased during World War II but decreased soon afterwards, prompting further cuts. The railroads converted from steam to diesel in the 1950s. All three purchased substantial fleets of Budd Rail Diesel Cars, which lowered operating costs – but not enough to save most branch lines. A 1945–47 state report proposed suburban extensions of the rapid transit system, largely using railroad rights-of-way, with the expectation that most commuter rail service would be cut back to the rapid transit terminals or abandoned entirely. Prompted by the report, part of the BRB&L was reactivated as rapid transit in 1952–54 by BERy successor Metropolitan Transit Authority (MTA), and the Highland branch was converted to a rapid streetcar line in 1958–59.