The centre originally opened in May 1989, first replacing local boxes in the area, including the 1951 York power box. The 1951 box was at the time one of the largest route-relay interlockings in the world, its relay room 46 metres long by 10 metres wide, containing nearly 3,000 relays. It replaced seven mechanical boxes containing a total of 868 levers – the largest of which was Locomotive Yard, the largest mechanical signal box in the UK. York IECC also replaced the LNER power boxes at Northallerton, Thirsk Tollerton and Skelton Junction When the first stage of York IECC was completed in April 1990, its control area boundaries were Church Fenton, Low Gates, just south of Great Heck to Just south of Darlington on the ECML. In the early 2000s, the IECC was further extended to take in the 1960s Leeds PSB area, Church Fenton and the newly electrified lines to Skipton. The control area was further extended in 2011 with the closure of Moorthorpe and Hickleton signal boxes.
Control area
The IECC now has seven workstations: York North, York South, Leeds West, Leeds North-West, Leeds East, Leeds East Assist and Leeds Ardsley. The workstations are supplied with automatic route setting to assist with the signallers' workload. The overall control area is Danby Wiske on the ECML to north of Shaftholme Junction and from Gargrave /Bradford Forster Square/Ilkley/New Pudsey/Woodlesford/Cottingley/Bolton on Dearne/South Elmsall/Horsforth through Leeds station to York. Leeds station handles around 1,000 train services per day, and York around 420. The centre drives a number of Solid State Interlockings and older Route Relay Interlockings, for example some of the relay rooms provided for the 1983 Selby Diversion, which was controlled from a separate mosaic panel inside the old 1951 box before the area was controlled by the IECC. There is also a Westlock interlocking controlling the Moorthorpe/Hickleton area.
Other
Part of the centre's overview screens are displayed in the National Railway Museum at York. The most recent update to York IECC was at Christmas 2011, when there were changes to the track layout at the south end of the York station to improve the capacity of the station by providing an additional approach track from Holgate Junction. The updates required to the IECC and the SSI interlockings were undertaken by DeltaRail. By the end of 2016, signalling controlled by York IECC was due be transferred to the Rail Operating Centre located adjacent to the IECC building. However, most of this was delayed until the Christmas period over 2018/2019 and the IECC will then be decommissioned. The transfer was completed between 24th and 27th December 2018 The IECC building may also be demolished to make way for more platforms in station.
