The West End Line or New Utrecht Avenue Line was a surface transit line in Brooklyn, New York City, United States, running along New Utrecht Avenue and other streets between Coney Island and Sunset Park. Built by the Brooklyn, Bath and Coney Island Railroad as a steam line, it became a trolley line, along which elevated trains ran until the new elevated BMT West End Line opened. This route is no longer part of any bus line; its southern part (south of Bath Beach) was part of a bus route (the B64, which replaced the 86th Street Line trolleys, until 2010). In 2013, the B64 route to Coney Island was restored.
The Brooklyn, Bath and Coney Island Railroad, incorporated in 1862 with Charles Godfrey Gunther as president, opened the first part of its line, from 25th Street and Fifth Avenue to Bath Beach mainly along New Utrecht Avenue (then the Bath Plank Road), on October 9, 1863. The extension to Coney Island was opened on June 9, 1864, making it the first steam railroad to bring beachgoers from downtown Brooklyn. (The Coney Island and Brooklyn Railroad had been operating horse cars to the island since 1862.) At the Brooklyn end, the steam line ended at 36th Street and Fifth Avenue, where the BB&CI's own horse cars ran to a connection with those of the Brooklyn Central and Jamaica Railroad's Fifth Avenue Line and the Brooklyn City Railroad's Greenwood Line at 25th Street and Fifth Avenue. The odd double transfer was made necessary by the City of Brooklyn's refusal to allow the line to operate steam cars within its city limits.