Editing Overhead line (section)

===Overhead catenary systems in the United States===
The [[Northeast Corridor]] in the [[United States]] has catenary over the {{convert|600|mi}} between [[Boston]], [[Massachusetts]] and [[Washington, D.C.]], for [[Amtrak]]'s [[inter-city rail|inter-city]] trains. [[Commuter rail]] agencies including [[MARC Train|MARC]], [[SEPTA]], [[NJ Transit Rail Operations|NJ Transit]], and [[Metro-North Railroad]] utilize the catenary to provide local service.

In [[Cleveland, Ohio]], the [[RTA Rapid Transit|interurban/light rail]] lines and the [[Red Line (Cleveland)|heavy rail]] line use the same overhead wires, due to a city ordinance intended to limit air pollution from the large number of steam trains that passed through Cleveland between the east coast and Chicago. Trains switched from steam to electric locomotives at the Collinwood railyards about {{Convert|10|mi|km}} east of Downtown and at [[Linndale]] on the west side. When Cleveland constructed its rapid transit (heavy rail) line between the airport, downtown, and beyond, it employed a similar catenary, using electrification equipment left over after railroads switched from steam to diesel. Light and heavy rail share trackage for about {{Convert|3|mi|km}} along the [[Cleveland Hopkins International Airport]] [[Red Line (Cleveland)|Red (heavy rail) line]], [[RTA Rapid Transit#Blue, Green, and Waterfront Lines|Blue and Green interurban/light rail lines]] between [[Cleveland Union Terminal]] and just past East 55th Street station, where the lines separate.

Part of [[Boston]]'s [[Blue Line (MBTA)|Blue Line]] through the northeast suburbs uses overhead lines, as does the Green Line.

The [[Yellow Line (CTA)|Yellow Line]] on the [[Chicago "L"]] used an overhead catenary system for the west half of the route, transitioning to third rail for the east half. This was discontinued in 2004 when the entire route was converted to third rail.

On the [[San Francisco peninsula]] in [[California]], the [[Caltrain]] [[commuter rail]] system completed the installation of an overhead contact system (OCS) in 2023, to prepare for the conversion of its 160-year old [[San Francisco]] to [[San Jose, California|San José]] Peninsula Corridor to fully-electrified revenue service in September 2024.