Map of Thameslink and Three Crossrails

This post was last updated on 24 May 2022

The eleven lines of the London Underground form a network whose shape is iconic. But a network with a very different shape is gradually forming, composed of lines with a very different nature:

Thameslink, Crossrail 1, Crossrail 2 and a possible Crossrail 3

Thameslink

Thameslink is London's "Crossrail Zero", connecting rail services north and south of London with the help of 150-year-old tunnels. Its absence from the Tube map (until December 2020) has been the subject of discussion and controversy, but alongside the Crossrails it's a natural fit.

This map includes the Thameslink route from London Bridge to Maidstone and Ashford International, due to open in December 2019. Also shown are the limited-service routes to East Grinstead and Littlehampton. The map doesn't show stations like Hadley Wood, which Thameslink services currently pass through without stopping.

Crossrail 1

The Crossrail tunnel between Paddington and Abbey Wood opened in May 2022. Crossrail services are branded as the Elizabeth line, but this map gives it the name "Crossrail 1" to more explicitly associate it with the other Crossrail lines.

As well as showing Old Oak Common station (planned to be built as part of HS2), the map depicts three proposed extensions to the Crossrail 1 route, all shown with a dotted line. First of these is a direct link between Reading and Heathrow, which was consulted on recently by Network Rail.

Direct Crossrail connection from Heathrow to Reading

Second, the map shows an eastern extension of Crossrail from Abbey Wood to Gravesend. This proposal appeared in the Mayor's 2018 Transport Strategy and my 2040 Tube Map.

Crossrail to Gravesend

Third, the map shows a connection between Old Oak Common and the West Coast Main Line tracks between Wembley Central and Euston, which allows Crossrail services to run to Watford and Tring. The proposal is discussed by London Reconnections here.

Crossrail to Tring

Crossrail 2

Crossrail 2 is Crossrail 1's proposed successor, very much following the same philosophy. The route would run from south-west to north-east, connecting suburban routes in Surrey with those in Hertfordshire. No commitment to Crossrail 2's funding has yet been made, but the route has the backing of London's mayor (and Shaun Bailey, who challenged him in the 2020 2021 mayoral election).

The map also shows (as a dotted line) a proposal for Crossrail 2's "Eastern Phase". This proposal would create a new Crossrail 2 branch, running in a tunnel through Hackney and Stratford and then linking with the existing Essex Thameside lines which currently run to Fenchurch Street.

Crossrail 2 – Eastern Phase

This proposal is discussed by Railfuture here. Although a section of tunnel to Hackney Wick is part of Crossrail 2's safeguarded route, the most recent official Crossrail 2 proposals don't include the eastern branch, only treating it as a potential future option.

Crossrail 3

There is no proposed Cross-london railway line which bears the name "Crossrail 3" in an official capacity. Serious energy is focused on delivering the first Crossrail and making the case for a second, while any talk of a third Crossrail is much, much more speculative.

One place to look for potential Crossrail 3 schemes is a 2016 report to the National Infrastructure Commission, "Review of the Case for Large Scale Transport Investment in London". The report discusses Crossrail 2 (including the possible eastern branch) in detail, but it also spends a moment looking further ahead to Crossrail 3.

The report looks at two schemes. One is a connection between Stratford and East Croydon, depicted on the map above. Railfuture are campaigning for this under the name "Thameslink 2".

The other scheme examined by the report is a southern extension of the Northern City Line, London's "forgotten Tube line" which currently terminates at Moorgate. The new section of tunnel would serve Cannon Street and Waterloo before surfacing. Having only two new underground stations would make it cheap by Crossrail standards: by comparison, Crossrail 1 will open with ten new stations, nine of them underground.

Crossrail 3 – Waterloo to Moorgate

These are not the only visions of Crossrail 3 which have been put forward. Many have suggested that Crossrail 3 should be another north-south route from Waterloo to Euston. CityMetric discusses a Crossrail 3 running from south-west to south-east. The Environmental Transport Association suggests something similar, a "Southern Crossrail" formed by linking Waterloo with Waterloo East. Brian Butterworth's 2050 Tube Map, based on London Infrastructure Plan 2050, draws Crossrail 3 from Waterloo to Barking.

The future of the Tube

This map definitely shouldn't be taken as a concrete prediction of the future. If Crossrail 2 goes ahead, there is a good chance that its route could change. Crossrail 3 could follow any of a number of different paths across London.

But the map does help to illustrate the design philosophy which London's underground railways are increasingly moving towards. As tunelling technology improves and space for new surface railways becomes ever-scarcer, it becomes more cost-effective to use tunnels to connect existing railways, rather than build lines with narrow tunnels and their own dedicated surface sections. London is likely never to build another Tube line like the Northern or Jubilee lines. the future of London's transport sits elsewhere.