What Would Happen If The Northern Line Split In Two?

Rachel Holdsworth
By Rachel Holdsworth Last edited 23 months ago
What Would Happen If The Northern Line Split In Two?
Photo by Daniel Coyle from the Londonist Flickr pool

The idea of splitting up the Northern line isn't crazy. It originally was two separate lines — the City and South London Railway (running from Morden via Bank to Camden Town) and the Charing Cross, Euston and Hampstead Railway (running from Kennington to Edgware via Charing Cross, with a spur to Archway from Camden Town).

The name "Northern line" came into existence in 1937, bolting together all the various bits that confuse tourists, and Londoners who aren't paying attention, to this day. Wouldn't it be easier to untangle it and have simpler routes?

That's something Transport for London have been wanting to do for a while — and a document from July 2015 (PDF) proposes the Northern line will be split by April 2023. By getting rid of the bottleneck at Camden, where lines cross over, TfL thinks it can run 33 to 36 trains per hour. At the moment, only the middle sections approach that kind of frequency.

Before that can happen, Camden Town station needs significant upgrade works, as does Kennington, because these stations would become major interchanges between the two lines.


So we've got two new lines coming. Where would they run?

It seems almost certain that the Edgware branch would run via Charing Cross and terminate at Kennington. Or, quite possibly, terminate at Battersea Power Station — the way TfL has drawn the map of the extension it's quite clearly running on from the Charing Cross branch. The new stations at Nine Elms and Battersea are scheduled to be ready by 2020.

The other line would run from Barnet via Bank down to Morden.


Now we're getting to the interesting bits. What would these new lines be called?

It's tempting to keep the Northern line name for the Edgware-Kennington/Battersea line and call Barnet-Morden the Southern line. This, however, is a bit boring (though still better than naming a line after another member of the royal family).

How about following the portmanteau method, like the Bakerloo? We could have the Burntbat line; the Tott-Toot line (after Totteridge, not Tottenham Court Road); the Colinloo? Or what about the King's Elephant line; Borough & Barnet; we could rename Charing Cross and get the Hampstead & Trafalgar line.

We can also foresee a campaign for the Mornington line, after the marvellous Radio 4 game. Anyone who suggests the City line gets banished for sheer dullness.


The current tube map is a big ol' mess. We already have 11 solid colours, plus four more in stripes (think DLR and Overground) and that's before Crossrail the Elizabeth line turns up in purple.

One of the lines will probably stay black; probably whichever keeps the inevitable Northern line moniker. But what happens to the other one? There could be an option of going for black and white stripes; but striped lines are generally kept for more rail-like services.

There aren't that many colours left. We could have a light green, maybe. Or a darker or lighter shade of purple than Crossrail the Elizabeth line Crossrail. Whatever happens, it'll look bloody awful. Harry Beck never imagined the tube map would be so busy — time for a complete overhaul?

Last Updated 22 May 2016


There's also one more thing to consider: Night Tube. The night service on the Northern line is scheduled to run from High Barnet and Edgware to Morden... via Charing Cross. So when (if?) the Northern line does split into two separate lines, what happens to the Night Tube services? Will the trains be re-routed via Bank instead, leaving the Charing Cross branch without a service? Will they terminate the trains at Kennington (or Battersea), leaving the line to Morden without a service? Will the Night Tube "follow" the split and have a night service on each separate line (Edgware - Charing Cross - Battersea and High Barnet - Bank - Morden)? Or will the trains keep running as they would before the split, creating a "hybrid" line (Edgware/High Barnet - Charing Cross - Morden)? Each option has its own advantages and disadvantages but there doesn't seem to be an obvious solution. (Note that the split has to go High Barnet-Bank and Edgware-Charing Cross because if it went the other way around, the High Barnet-Charing Cross line wouldn't have a major depot; the two main Northern line depots are at Morden and Golders Green.)

Also, regarding the names: I have always assumed that the name "Northern line" would be given to the High Barnet-Morden route, for two reasons. Firstly, High Barnet is further north than Edgware. Secondly, the name "Northern line" comes from the Northern Heights plan in the 1930s, which was focused around the Highgate and Finchley areas, so it would make sense to give the name to the line that goes through there. But, you never know, TfL might disagree on that. And there's still the unanswered question about the name for the Edgware-Battersea line. Maybe just call it "The Other line"? As for the colour: why not use the same colour as they used for the East London Line? It's not used anywhere else and it doesn't clash with any other colours already on the map so it seems like the perfect choice.

Anyway, no matter what the outcome is, I am looking forward to see the line split. I know I've said it in the comments before, but I really think this should happen as soon as possible.

Jake M Peters

Definitely in favour of honouring I'm Sorry I Haven't A Clue with the Mornington Line.


The Paris metro already seems to have more colours than the LU, with pinks and purples and such. Is London's decorative sense so much inferior to Paris's?

Maybe if one stays black the other - probably the one through the more expensive postcodes - should be white?


Charing Cross line, and the City line. Easy?


Re the tube map: yes, time for a complete overhaul, the sooner the better.

Greg Tingey

Certainly time for a complete overhaul of the tube & the "London Connections" maps.
IMHO the proposed enlargement at Camden Town is not going to be big enough, with approx 50% of people interchanging there, as opposed to the about 15% now ( Most people wait for an "appropriate" train at present )


It's not the way TfL have drawn the map which means that it is Charing Cross trains which will go to Batterea Power Station - it's the physical reality. The new tunnels to Battersea branch off from the Kennington loop (built to allow trains to turn round at Kennington without reversing), which can only be reached from the Charing Cross branch - as can clearly be seen here http://carto.metro.free.fr/car... . That's why now it's only ever southbound trains on the Charing Cross branch terminate at Kennington - and it's why there will never be a service from Battersea Power Station through the City branch.

Couple that with the point Mudshoot made about the location of depots, and the split pretty much has to be Mordern to High Barnet via Bank and Battersea Power Station to Edgware via Charing Cross.


It's only one destination, but "Battersea Line" sounds terrifically evocative - I would go for that. Then the other half the Northern Line. "Southern Line" is too boring. Also, not that I really want it, but a mustard yellow is a colour that hasn't been done yet...

Louis Davies

Lime Green is probably the best colour not yet taken although Magenta could also work. Calling the line through Tooting 'Southern line' may be boring but I would take that and run considering they'll probably call crossrail 2 'Charles' although I'd call it Barting or Finchdon.


Liney McLineface ?


Diamond line? Anyone?

native new yorker

How does London pay for all these subway expansions?

Riccy Jeffs

THE BRUNEL LINE, of course. After Marc and his son Isambard who are responsible for the Thames Tunnel, the oldest tunnel in the oldest underground system in the world. They are worth a Google as their engineering projects were quite spectacular.



Ahsen Khan

No the should keep and extend it

I also want to see the northen line extended all the way down to gatwick


The Eastern half can't really be the City Line if the H&C is to continue with its current Moniker. While it might be boring, I would encourage TfL to have a West End Line (Battersea to Edgware); the City Line (Morden to High Barnet/Mill Hill East); and the Hammersmith Line (Hammersmith to Barking).


The idea that TfL have run out of colours for the tube map -- have you seen a TfL bus map?

Pinkas Lee

I truly hate the idea of splitting the line. I love that fact that standing on Golders Green platform I have a good choice - central London or the City - it's wonderful! and I don't mind waiting few more minutes to get the alternative branch.

Saying that, if the line were to split, I would choose the - yes - boring option -
"Charing Cross Line" & "The City Line".

But please don't split them up!


The planned upgrade to Camden will be to accommodate increased passenger numbers only. On the map above it shows a tube line to Clapham J, this will not happen as demand at Clapham J would be to high for this service had push the existing line to capacity. This is why we need Crossrail 2! Regarding naming of a tube line, let hope they can be more imaginative then The last one...i would have prefered Tuby Mctubeface or more suitabily one of the many black, indian or female role models this cuntry has been honoured with!!

Luca Trifan

Why don't they make an interchange at Vauxhall station?


I think the northern line is unique and should keep its name, if it has a name change and splits I think the same should be done for the district because it gets very confusing at Earls Court and the central line therefore can be split into two as well.