From a point in Secaucus, just south of the Hackensack River bridge near the former Harmon Cove station, to a point in East Rutherford north of the Rutherford station, the Bergen County Line uses the former Erie Railroad Main Line. This portion was opened in 1833 by the Paterson and Hudson River Railroad and leased by the New York and Erie Rail Road in 1852. The rest of the line, from East Rutherford north to Glen Rock, opened in 1881 as the Bergen County Railroad. Until the late 1950s, the main function of the Erie's Bergen County Cutoff was as a freight bypass of the at-grade Main Line through Passaic. Commuter service was relatively minor. In 1963 the Lackawanna Boonton Line up to Paterson became the new Erie Main Line. This was due to the abandonment of the Main Line section through downtown Passaic and also due to the fact that Interstate 80 construction used the old Boonton Line right-way in Paterson. The old Main Line up to Rutherford was now exclusively part of the Bergen Line. Prior to the opening of Secaucus Junction in 2003, Bergen County Line trains used a longer stretch of the old Erie Main Line in Secaucus, extending south to Croxton Yard and a merge with the former Lackawanna Boonton Line. A curving track was built between the HX Draw at Hackensack River and the Main Line north of Secaucus Junction to allow Bergen County Line trains to use Secaucus Junction.
On February 9th, 1996, a Bergen County Line train collided with a Main Line train killing 3 people.
Service
Approaching Secaucus Junction, a westbound train headed for the Bergen County Line will use the more northerly pair of tracks, designated G and H at the transfer. West of the transfer, these tracks diverge from the Main Line over a new right-of-way opened on December 15, 2003, connecting the Main Line with the Bergen County Line. During this stretch, the Hackensack River is to the left, while industrial plants on Meadowlands Parkway are to the right. A former station, Harmon Cove, was located nearby along the old Erie right-of-way and served the high-rise apartments nearby between 1978 and 2003. Soon the train joins the old Erie Main Line right-of-way and crosses the Hackensack over HX Bridge, a two-track bascule draw. For the next two miles, the train crosses the Meadowlands, under the New Jersey Turnpike western spur with the Meadowlands Sports Complex in East Rutherford visible in the distance to the right and a new development beginning to take shape in Rutherford, to the left. Here, the track parallels Berrys Creek and eventually crosses it just before passing below Route 3. Beyond Route 3, the landscape changes to industrial. Office buildings line the side of the track, some serviced by sidings. The Pascack Valley Line soon splits off to the right at Pascack Junction, and the train then crosses Route 17 and approaches the Rutherford station. For a half-mile the train passes residences on either side, then swings right, abandoning the old Erie Main Line at, and passes through industrial areas with several grade crossings. Soon, the tracks form the border of Carlstadt and Wallington. Presently the train passes Wood-Ridge and South Hackensack before reaching the Wesmont station, which opened on May 15, 2016. The train then swings left, crossing the Saddle River, and then right, into Garfield reaching the Garfield station. The train continues northward through Garfield, passing homes, businesses, and Dahnerts Lake County Park before reaching the Plauderville station at Midland Avenue, the border between Garfield and neighboring Saddle Brook. Shortly after passing beneath U.S. Highway 46 the track becomes the border of Saddle Brook and Elmwood Park, once again crossing Midland Avenue. Interstate 80 passes above the train, which then crosses the Garden State Parkway. The Broadway station in Fair Lawn straddles a border formed by the track and Route 4. In Fair Lawn, the line is paralleled by Plaza Road, named for Radburn Plaza, the commercial area serving the Radburn development for which the borough's more northerly station is named. The line crosses below Route 208 before reaching Radburn. Beyond the station, the train passes housing to the right and industry to the left, with a spur to a Nabisco plant. Next is the Glen Rock-Boro Hall station which like its Main Line counterpart is on Rock Road. The lines merge a short distance north of this point at Ridgewood Junction. The trains will continue north to either Waldwick or Suffern, and some peak trains will terminate at Ridgewood, which is the first station after the two lines join.
