please empty your brain below

I think the thing you want is a Voronoi diagram/map. This takes a set of seed points (stations in this case) and makes polygons representing all points closest to each seed.
Random guess for smallest hinterland : Bank
Sounds great. I built a tool that shows UK supermarkets on a map in a similar way to how you might want to draw your stations:

I wrote more about it at and and the code is at

Someone could tinker with it to draw the map for London stations. You would need a list of the stations along with Lat/Long Coordinates.
Sounds a fun wheeze. Look forward to it!
This sounds right up Oliver O'Brien's street.

Are you accounting for any stations that open during the life of the project? I don't think Crossrail will have any effect, but you might find yourself with an additional Underground or Overground station, depending on how long it takes you.

dg writes: I'll be adding Woolwich to the list in December.
There is demo here where you can build a Voronoi diagram using Google Maps:
Simon and Chris - ah that's what it's called! Yes, a Voronoi diagram is exactly what I'm after.

I know a list of station coordinates exists, because a couple of years ago Georich came up with this viral map showing everywhere in London that's more than one mile from a station.
Excellent idea on the Random Stations.
Well, this is close. London Tube Map with Voronoi

But not the first. For example.
Is Hampton Court on your list?

dg writes: No.

Does "any other station" include stations outside London and so not on your list?

dg writes: Yes.
Andrew's link has the station locations here
There are various station lists around. Many seem to include only Underground, or Underground and DLR.

TfL publishes station location data in KML and XSD formats here: but you need to register for the full data. No idea why... I'll leave this to the experts :)
I don't think it'd be Chelsfield, Knockholt would have a bigger catchment I'd have thought?

dg writes: It would, except most of Knockholt's catchment is outside London, and I'm not going there.
And that’s even if the voronoi polygon crosses say the river or a canal?

dg writes: Yes. This is geometry, not reality.
Please let there be a jam jar!
Sounds interesting! I’ll draw you up a Voronoi Map today at work in GIS. Similar stations will be separated (eg multiple West Hampstead) but I’m sure you could ignore some of the lines!
I think Stratford has a good chance for smallest area, what with the international station, the high street DLR station and Pudding lane DLR it has to just be half of Westfield, a couple of roads and half the stratford centre?

dg writes: Stratford's area spreads to 100 acres. Leicester Square and Bank are under 50.
Stratford's area
Wot, no jam jar?!

Sounds like an amazing project.
As described, this sounds fairly lame.
But I'm sure your realisation of it in photos, facts and prose will be as entertaining as your readers have come to expect.
Looking forward to it already.
If I was at work I’d ping you across the x-y coordinates for all the stations. I had them all cleaned up last year my a graduate to get rid of duplicates as if you use the main tfl/nr datasets you’d have almost 800 stations! I think I had slightly more than 588 though. If you still haven’t got this by Monday let me know.

It’s surprisingly hard to determine how many stations there are in London.
Unfortunately this means I'll have to rename myself Limehouse.

Surely though due to the DLR's presence in East London, won't there be a lot of tiny areas in Tower Hamlets and Newham? I'm not sure if there will be much dg can write that's new in Bow Church's area, for example.

dg writes: I've written dozens of posts about Bow Church's 100 acres. I'm sure I'll manage again. :)
You should visit Hartlepool if you've never been before, it's lovely.
Here's my go at the areas for the 588:

Although I have the same number, my types don't quite line up - I have 4 fewer LU stations, 1 fewer OG station and 5 extra NR stations.
List here:
Smallest is Centrale (0.1 sqkm), largest is Upminster (24.4 sqkm).
Thanks Ollie, that's brilliant!

Please don't let that stop anybody else :)
*idly wonders how much employer time is being eaten up today by commentators helping DG out* ;)
Hey! What about us Women Who Breathe Railways?

dg writes: You'll be disappointed too.
This sound a bit like Sam Cullen's INNside Track blog at
He successfully completed his first mission of one pub per tube station (with allowance for some stations being located in 'pub deserts'), then started a similar exercise for National Rail stations in London, alas coming to a halt after West Croydon.
Loving that map from Ollie. Thank you!

Are there any spots that are equidistant to 4 (or 5) stations? Or if not what's the closest?
I think the missing Overground station is Romford (listed as NR)
Thanks for the list of stations, Ollie!

I've double checked my list against yours, and removed a few errors I had, and I now have a list of 590 stations, not 588.

The discrepancy is explained by the fact that I've deemed Bank and Monument to be separate stations, and Hackney Central and Hackney Downs to be separate stations too.
Jam jar not big enough or has it been recycled?
Boroughs I'll be visiting most:
×40 Croydon
×32 Westminster
×28 Bromley, Newham, Tower Hamlets

Boroughs I'll be visiting least:
×6 Barking & Dagenham
×9 Havering
×10 Bexley, Kingston, Sutton

Not that I'll ever get round to all of them.
Thanks DG. I've updated the polygons for those extra two stations, and fixed the categories at/near Romford. Also worked around a weird QGIS bug which made a few of the polygons overlap, near the edge of London. Revised list at
Hertfordshire and Essex are excluded, but not Buckinghamshire?

dg writes: Also Buckinghamshire.
Ollie - you've also missed westcombe park
Also, looking at Ollie's map, how do you treat an area that is inside london but closest to a station outside of london? Eg area near Denham
Sounds great.

These comments are good too. DG readers are such a talented bunch.

So what is the smallest & largest area?

dg writes: See comment at 10:13 (and smile)

Squinting at the map, Centrale tram stop looks pretty small. I've been there, and writing something interesting will be a challenge even for DG. I'm looking forward to it.
some people have too much time on their hands...still it will no doubt be interesting
Nice map! I'm not spotted any four or five way vertices but there are some short chords. The nearest I have seen is south of West Acton.
Your yellow overlay of the area you'll be exploring is roughly the shape of the state of Nevada, with Area 51 being located in the middle of the Round Pond. Let us know if you find any aliens floating about out there.
Ollie's map is great, and I hesitate to criticise because I could never have generated it.
But it's not quite accurate along the Thames. There are areas (such as a small riverside sliver of Deptford) shown as nearest DLR stations on the Isle of dogs - whereas in reality the Thames is a total barrier so the division Line shown isn't true.
The santander cycle hire maps round here make the same error, with a '5 minute radius' drawn on the map, completely ignoring the detail that you can't cycle over water.

dg writes: The map is geometrically correct, and if Mudchute ever comes up I will indeed be popping across the river to Deptford.
I still hope that, just once in a while, your Random Station hinterland will include a mention of one of London's Lost Telephone Exchanges !
@Frank F (9:35 am):
Fairly lame? DG will be fairly lame if he walks round all 591 station areas in a short time!
Both maps necessarily reduce each station to a point. This has an odd effect on Walbrook, where the new entrance to Bank station next to the Mithraeum is shown as closer to Cannon Street station than to Bank itself!
I’d been wondering whether random rail lines would be worth a series, as every branch and extension tells a story in geography and history, but this is brilliant.

Not many triangles. Can only find Drayton Green (bounded by Castle Bar Park, Hanwell and West Ealing), but I’m sure there are others. Wonder which area has the most sides (ignoring the clipping from the Greater London boundary).
I like the way the polygon maps reveal those locations that are annoying equidistant from three or more stations.
At a rate of two stations a month, this project would take until the 2040s to complete, so don't expect me to ever finish it.
Following from timbo’s comment there are one or twot more multiple entrance stations where the single point causes some distortion. Blackfriars is the most obvious, but East Croydon will als be slightly affected.
This latest blog seems to have attracted more than the usual quota of geeks. Not that i've anything against geeks. Lovely folk. Give you the cardigan off their back...
I would have guessed west indiaquay or Canary Wharf Dlr would have been smallest.
I hope Erith comes up: Good luck 'popping across' to Tilbury Coldharbour Lane industrial estate. It looks like a great place for the curious, though.
I would dispute Battersea Park's Overground designation on the map in favour of Other NR.

There must also be a 'closest pair of stations across a category border, such as Clapham High Street / Clapham North
I know it's too late now but does anyone else think doing all the Bus Stop Ms in London would have been a good idea?

dg writes: I've done ten. That was enough.
Well done everyone on the Voronoi stuff! Classic DG.
The maps confirm something I always suspected about my old place in Croydon: that it was almost exactly equidistant from West Croydon, Thornton Heath and Selhurst stations.

TridentScan | Privacy Policy