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Redrawn Tube Map – Out of Station Interchanges

Future Tube Map - OSI

Click here to view a large version of the map

One more post about my redrawn London Tube Map before I move onto other projects.

One thing that bothered me about the map as I worked on it was the way that no visual distinction is made between interchanges that are made within the fare control area – that is, simply moving from one platform to another – and those that require you to exit one station and re-enter at another nearby station, preferably by tapping out and then back in again with an Oyster card. There are many such interchanges in London, some of which are well-known and others which seem to be a deep, dark secret known only to the most seasoned of commuters. They’re officially known as Out-of-Station Interchanges, or OSIs, and they even have time limits defined to set boundaries for “reasonable” interchanges between stations.

It seemed to me that the distinction between a normal interchange and an OSI is fairly important, so I set out to see if there was an easy way to distinguish between them on the map. In the end, I came up with what I think is an elegantly simple solution: retain the white “corridor” connector for normal interchanges, but use a thinner black-only connecting line for OSIs. The white connector visually joins all the interchange dots at a station as a unified whole, while the black connector separates them, immediately implying a more complex journey.

Walthamstow OSI

Above is a great example of how the new connector works. The Underground and Overground platforms at Walthamstow Central are connected by a normal interchange symbol, while the short walk to the nearby Walthamstow Queen’s Road station is indicated with a black OSI connector. Another OSI connector can also be seen at the Seven Sisters/South Tottenham interchange. Hackney Downs and Hackney Central were recently linked by a footbridge inside the fare control area, so they’ve been upgraded to a “true” interchange symbol.

Paddington OSI

Showing out-of-station interchanges consistently and properly did require one fairly major reconfiguration of route lines at Paddington. Here, I’ve brought the Bakerloo line down to join with the District and Circle lines at the Praed Street section of the complex. The short walk through the National Rail station to reach the Hammersmith & City/Circle line platforms is now neatly indicated with an OSI connector.

The Bakerloo flips back up to the north again after Paddington to place Edgware Road in the correct position relative to the other Edgware Road. While this pair of stations could technically have been shown as an OSI, I’ve chosen not to: it’s not a very convenient  or useful place to change with Paddington and Baker Street nearby, so the map rightfully discourages their use as an interchange. Note also the OSIs at White City/Wood Lane and Shepherd’s Bush.

Not shown, but also useful: an OSI connector between the two Hammersmith stations. Have a look at the big image of the map to see all the OSIs that I’ve identified, and let me know if you think I’ve missed any.

While you’re there, have a look at the potential future additions to the Tube Map that I’ve added just to give you something else to look at: the Metropolitan line extension to Watford Junction, the Bakerloo line extension to Hayes via Old Kent Road (which may or may not ever get past Lewisham) and the Battersea Power Station extension of the Northern line, which is nicely lined up in case it gets extended further to Clapham Junction. Yes, I’m very aware that any future Tube Map will also have to deal with all the new Overground and Crossrail 2 lines, but that’s beyond the scope of this project (at the moment).



  1. Si

    While not an OSI, West Ealing, rather than Acton Main Line, needs the NR symbol.

    Ignoring stations not on the map (including NR ones of the same name like Marylebone and Cannon Street), taking this list and putting a cut off of 0.3 miles (the same as the Walthamstow and Hackney interchanges) we have:

    Aldgate – Tower Gateway
    Archway – Upper Holloway
    Brondesbury – Kilburn (West Hampstead makes not worth showing?)
    Camden Town – Camden Road
    Dalston Junction – Dalston Kingsland (Canonbury makes not worth showing?)
    Edgware Road – Edgware Road (already rightly ruled out)
    Euston – Euston Square (this is LU as well as NR)
    Kenton – Northwick Park
    Manor Park – Woodgrange Park (the other one is slightly shorter)
    New Cross – New Cross Gate will meet my criteria post Bakerloo line extension.

    And as you have the Tower (Tower Hill makes sense, but Gateway less so) – Fenchurch St marked, here’s the NR (not Overground) stations with osi with TfL stations (no upper limit on distance) listed by LU station.

    Aldgate: Fenchurch Street
    Baker Street: Marylebone
    Bank: Cannon Street, Fenchurch Street (quite long), Liverpool Street (not needed?)
    Bounds Green: Bowes Park
    East Putney: Putney
    Edgware Road SSLs: Marylebone
    Embankment: Charing Cross, Waterloo, Waterloo East (this last one isn’t needed)
    Lancaster Gate: Paddington
    Mansion House: Cannon Street (ignore as closer station on lines)
    Monument: Fenchurch Street (ignore as closer station on lines)
    Southwark: Blackfriars, Waterloo East
    Sudbury Hill: Sudbury Hill Harrow
    Waterloo: Waterloo East

    • Si

      I forgot Canary Wharf JLE to Heron Quays. And the Canary Wharf stations are linked with OSIs (including Crossrail when it opens, which probably will also have an OSI with Poplar).

  2. K.o.R

    Great map design.

    Nitpick: I’m sure Canary Wharf DLR to Canary Wharf Jubilee is an OSI, since you have to leave through the Jubilee ticket barriers.

  3. marek

    As I understand it, the Northern line extension won’t quite work as you have shown it at Kennington. It is true that trains from Battersea Power Station will only be able to reach the Charing Cross branch, it is not true that trains from the Charing Cross branch will only be able to reach Battersea Power station – they can and some probably will continue to Morden (the layout shown on Carto Metro makes clear why that is so).

  4. Pingback: Project: Redrawing the London Tube Map | Cameron Booth

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