Coordinates: 40°42′47″N 74°11′12″W / 40.7130°N 74.1866°W
The pre-1997 connection is at bottom left of photo looking east; the new connection was built just to the north.
The Lehigh Line Connection connects Amtrak's Northeast Corridor (NEC) with the Conrail Lehigh Line two miles south of downtown Newark, New Jersey. It leaves the NEC at Hunter Interlocking, and the line is sometimes called the Hunter Connection. It is used by New Jersey Transit Raritan Valley Line trains and is a 1997 replacement for an older connection.  It splits from the NEC just north of the former connector, with wider curves (45 mph instead of 15 mph) and catenary wire that for now serves no purpose.
The old connection had a single track with older overhead wire and Pennsylvania Railroad (PRR) signaling. Until 1961 Lehigh Valley Railroad (LV) passenger trains bound to/from Pennsylvania Railroad's station in Manhattan, such as the Black Diamond, used the connection to reach their own railroad from the PRR main line. At the top of the hill at NK interlocking, LV diesels exchanged the train(s) with PRR electric locomotives.