Editing IND Concourse Line (section)

== Description and service ==
The following services use part or all of the IND Concourse Line:<ref>{{NYCS const|serviceguide}}</ref>
{|class="wikitable"
!rowspan=2|&nbsp;
!colspan=2|Time period
!rowspan=2|Section of line
|-
!rush hours
!other times
|-
|{{Rint|newyork|B}}
| colspan="2" align="center" |local
|south of [[Bedford Park Boulevard (IND Concourse Line)|Bedford Park Blvd]]
|-
|{{Rint|newyork|D}}
|align=center|express (peak direction only)
|align=center|local
|entire line
|}[[File:175 Concourse line underpass jeh.JPG|left|thumb|Passing over 175th Street]]

The Concourse Line runs north to south through the Bronx and portions of Harlem, parallel to the mostly-elevated [[IRT Jerome Avenue Line]] which lies between two and four blocks to the west for its entire length in the Bronx.<ref name="NYTimes-OurGreatSubway-IND2ndSystem-1929" /> Due to the steep topography of the neighborhoods surrounding the [[Grand Concourse (Bronx)|Grand Concourse]] (under which most of the line runs), several stations were built with entrances both above and below the platforms, including [[167th Street station (IND Concourse Line)|167th Street]] and [[Kingsbridge Road station (IND Concourse Line)|Kingsbridge Road]]. Because the line also connected with [[Yankee Stadium (1923)|Yankee Stadium]] at [[161st Street–Yankee Stadium station (IND Concourse Line)|161st Street]] and with the former [[Polo Grounds]] at [[155th Street station (IND Concourse Line)|155th Street]], there were also several switches and a storage track to accommodate additional trains during game days.<ref name="p1114643923">{{cite news |date=25 June 1933 |title=City Subway Extension, Opening Saturday, Gives New Bronx Link: 6½-Mile Section Follows Concourse, Dips Under Harlem, Joins Independent's Line at 145th St. Underground Stations at 2 Baseball Parks; New System Expected To Be Less Noisy, Cooler in Summer Where Passengers Will Go Upstairs to Board Subway Trains |page=A5 |work=New York Herald Tribune |id={{ProQuest|1114643923}}}}</ref>

The line begins as a two-track line at Norwood–205th Street, running east-to-west underneath East 205th Street, then under private property, then for a short portion under Van Cortlandt Avenue.<ref name="tracks">{{NYCS const|trackref|trackbook3}}</ref><ref name="NYTimes-INDCncrse-205StRouting-June1929" /><ref name="MTAMap-VanCourtland-Botanic-FordhamPlz-2015">{{Cite NYCS map|neighborhood|Van Cortlandt Park}}</ref><ref name="NYTimes-INDEastSide-April1929">{{cite web|title=City Soon to Launch $600,000,000 Subway for the East Side – Delaney to Submit Plans for New System Including the Bronx in Two Months|url=https://timesmachine.nytimes.com/timesmachine/1929/04/05/95904066.pdf|work=[[The New York Times]]|access-date=November 4, 2015|date=April 5, 1929}}</ref> As it travels west, a center track forms which leads to the [[Concourse Yard]]. The line then curves south at [[Mosholu Parkway]] to the Grand Concourse, from which it derives its name, at 206th Street.<ref name="tracks" /><ref name="NYTimes-INDCncrse-205StRouting-June1929" /><ref name="MTAMap-VanCourtland-Botanic-FordhamPlz-2015" /> Two tracks from the Concourse Yard arrive between the two revenue tracks with switches and [[diamond crossover]]s between all four of them before the yard tracks merge to form the center track at the [[Bedford Park Boulevard (IND Concourse Line)|Bedford Park Boulevard]] station.<ref name="tracks" /><ref name="NYTimes-INDCncrse-205StRouting-June1929" /> The center track was intended to be used by southbound express trains in the morning and by northbound express trains in the afternoon.<ref name="p1114643923" />

South of Bedford Park Boulevard, after some crossovers, the two outer tracks depress into a lower level and merge into a single center express track, while the center track splits to become the local tracks. The line then runs south with [[diamond crossover]]s at [[Tremont Avenue (IND Concourse Line)|Tremont Avenue]]. Due to the terrain, the vicinity of [[174th–175th Streets (IND Concourse Line)|174th–175th Street]] station is uniquely built both underground and over 175th Street. Between [[170th Street (IND Concourse Line)|170th Street]] and 167th Street are more switches and crossovers, with a lay-up track adjacent to the Manhattan-bound local track.<ref name="tracks" /> The line curves west before 161st Street–Yankee Stadium and crosses the [[Harlem River]] into Manhattan via the '''Concourse Tunnel'''. There is one more stop, 155th Street, before the line curves south under Saint Nicholas Place, continuing under Saint Nicholas Avenue south of 148th Street.<ref name="tracks" /> The Concourse Line then serves the lower level of the [[145th Street (IND Concourse Line)|145th Street]] station and joins the [[IND Eighth Avenue Line]] south of the station.<ref name="p1114643923" /><ref name="tracks" />