Hitchin Flyover | |
|---|---|
A Thameslink Class 700 crossing the flyover | |
| Coordinates | 51°58′12″N0°15′49″W / 51.96993°N 0.26355°W /51.96993; -0.26355 |
| Carries | Down Cambridge Flyover line |
| Crosses | East Coast Main Line |
| Named for | Hitchin |
| Characteristics | |
| No. oflanes | Single track |
| History | |
| Built | 2011–2013 |
| Opened | June 2013 |
| Location | |
![]() Interactive map of Hitchin Flyover | |
TheHitchin Flyover is agrade-separatedsingle-track railway viaduct nearHitchin,Hertfordshire,England, which carries theDown Cambridge Flyover line[1]: 238 over theEast Coast Main Line. Constructed between 2012 and 2013, it connects the westernmost track of the East Coast Main Line with theCambridge line. The flyover was built to increase the throughput atCambridge Junction,[1]: 209 a congestedflat junction, which put severe constraints on capacity on both lines.
Hitchin Flyover & Cambridge Junction | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
The flyover consists of a 1.41 miles (2.27 km) single-track electrified railway line, including both sections of embankment and a viaduct that carries theDown Cambridge Flyover line over the four tracks of the East Coast Main Line.[2][3][1]: 238 The flyover line diverges from the East Coast Main Line atCambridge Junction,[1]: 238 which is 0.7 miles (1.1 km) north ofHitchin railway station and 160 yards (150 m) south of the bridge that carries the East Coast Main Line over theRiver Hiz.[2][3] The flyover passes over the East Coast Main Line on a 22-span 870 yards (800 m) viaduct,[4] before joining theDown Cambridge line towardsLetchworth Garden City atHitchin East Junction.[1]: 238
The flat junction at the station remains in situ, which provides an alternative route for trains to access the Cambridge line from the Down Slow or Down Fast line.[1]: 238
Cambridge Junction (until 2013) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
TheEast Coast Main Line is a railway that runs betweenKings Cross inLondon andEdinburgh Waverley stations, and it forms a vital part of the UK's railway network.[5] The two most significant historical bottlenecks on the southern part of the route are the flat junction north of Hitchin, and ten miles to the south where the line's four tracks drop to two to cross theDigswell Viaduct.[6][1]: 206–208 This is because northbound trains had to cross the three other tracks in order to diverge from the East Coast Main Line and access theCambridge line atCambridge Junction.[1]: 209
In the 1970s,British Rail began modernising, rationalising, and electrifying the Great Northern route, which included alleviation of other bottlenecks on the route such as building a new flyover atWelwyn Garden City railway station.[7] In the 1980s, the construction of a flyunder to allow trains to avoid the flat junction were put forward, and land was set aside in order to construct it. However, the project was not seen to be feasible and did not materialise. This was followed in 1998 for afeasibility study which included various plans for flyovers, but once again none were taken further.[8]
| Network Rail (Hitchin (Cambridge Junction)) Order 2011 | |
|---|---|
| Statutory Instrument | |
| Citation | 2011/1072 |
| Dates | |
| Royal assent | 31st March 2011 |
| Commencement | 21st April 2011 |
| Text of statute as originally enacted | |
In 2006, theOffice of Rail and Road released a document entitledIssues in defining and measuring railway capacity, in which they discussed various capacity issues on the East Coast Main Line and projects aiming to mitigate them. Commenting on the idea of a flyover at Hitchin, they argued such a project "would undoubtedly make pathing more flexible and operations more robust"; however, they also said that it would not increase capacity as it was Digswell Viaduct that was the limiting factor on the number of services ran.[6]
The plan for the flyover was set out in theNetwork Rail (Hitchin (Cambridge Junction)) Order 2011, which was aStatutory Instrument permitting its construction by Network Rail. It was published on 31 March and came into force on 21 April.[2] In November 2011, the Department for Transport listed the flyover as an 'existing infrastructure project' in its annual National Infrastructure Plan, and expected that it would continue beyondControl Period 4, and therefore finish after 2014.[9]
Construction was completed in June 2013. Original plans were to build the embankment using aggregate trucked in from elsewhere,[10] but eventually it was decided to build up the embankment using chalk taken from the nearby Wilbury Hills, low-lying chalk hills forming part of theChiltern Hills, from less than 1 mile (1.6 km) away, removing the need for lorry movements along public roads. The chalk was quarried from just beyond the ancientIcknield Way, which at this point is a publicbridlepath betweenIckleford andLetchworth Garden City, and the contractor was required to refill and replant the quarry afterwards.[11][12][13] In order to minimise disruption to the East Coast Main Line, the viaduct section was installed duringnight-time possessions of the railway, before installing crash decking which allowed work on the viaduct to continue during the day when the line below was active.[4]
Since the embankment materials were locally sourced it also meant that the new embankment was effectively pre-seeded with poppies. This means the entire embankment is covered in red poppies during their flowering season giving the name to the location 'Poppy Bank'.

Services on the flyover were reported to have begun on 26 June 2013. At first, only three First Capital Connect services used the flyover each day; however, by the December 2013 timetable change, three-hundred drivers had been trained in order to allow six-hundred services to use the flyover rather than the flat junction.[14] As of the June 2025working timetables, all scheduled passenger trains travelling between Hitchin and Letchworth are pathed on theDown Cambridge Flyover.[15]
The introduction of the flyover increased journey times between Hitchin and Letchworth by approximately one minute; in contrast, southbound services were not affected as their route did not change. First Capital Connect amended their timetables for northbound trains to reflect this additional time.[16]
By January 2015 the only form of traction not to have used the flyover was electric locomotives (regular services areelectric multiple units);Union of South Africa became the first steam locomotive on the flyover when it movedempty coaching stock to Cambridge in preparation for a tour to York.