Geographically accurate underground tunnels - Google Maps

I noticed this, too-useful idea, but can't be sure which is right-Wiki has OSM on it, so it can't help for once.

I'm going to guess OSM, though-informed guess, because the earlier Tube lines had been built to follow under the streets following their line, to avoid costly wayleaves/demolition/compensation. So, as that City Branch was constructed slightly after that, the loopy alignment, which doesn't look on OSM to be following the line of streets at all, would be more feasible.

Wonder if an old Ordnance Survey Map would show them? Have a feeling they used to.

EDIT

Well, from Clive Bilson's site A History of the London Tube Map, you might find this pre-Beck 1924 pocket map useful to decide which one is correct:

1924 map

That looks like it represented what was on (or in this case, under) the ground, rather than the diagrammatic format we all know & love, why else stick a loop like that on the map unless that is how it lays? So, OSM has my vote as correct.

I'm sure I read once that the exact routing of the tunnels was not allowed to be publicised due to safety and security risks, and that actually there were no documents in existence that even showed the accurate positing of them.

Or is that all just belloni... !?

I have an old Barts Atlas of London, and it appears to show the actual tunnel routing. For example, at Shepherds Bush (Central) it clearly shows the strange Caxton Curve routing. 

Unless I am missing something, I fail to grasp what is the security risk in showing the routing. The tunnels are many feet underground, and I am not sure how a person(s) with sinister intentions would realistically be able to do anything on the surface to compromise  the integrity of the tunnel deep underground. 

And don't forget the incident at Redbridge(?) where the piling bit actually hit a train!

In either the late 90s or early 2000s the central London bus map showed the routings of the Underground tunnels.

My 5 year old London A-Z shows the sub surface tunnels as dotted lines.

here's a linkie to the Google version

here's OSM
www.openstreetmap.org/export#map=17/51.53480/-0.14055

The locations of the working shafts suggests OSM has got it wrong

The first map takes me to my local area not part of London and there is no means of moving the map around. This has happened quite often just recently so perhaps Google have changed something?

I have a map produced in 1944 showing all tunnels and subways beneath the City of London including the Post Office Railway. This is one of a series of maps produced by the City planners for post war development most of which was never carried out. Fortunately in the case of a proposed dual carriageway ring road around the City.

The Crossrail website features the alignment of the tunnels and gives a good representation of the alignments with other lines.

Herewith another map, from 2004. This is the physical features of London with actual physical Tube alignments superimposed on it:


mappy

That would indicate the Google alignment around Mornington Crescent is wrong.

Looking at the TfL web site Transparency page there is here a link to the Property Asset Register, which shows (if you zoom in - warning, it can be a bit slow), inter alia, the 'LUL Zone of Influence' where the tube lines run, against OS large (1:1250) scale mapping.

Here is the vector-based test-harness I use for viewing the OpenStreetMap tube data:

• www.paul.sladen.org/osm/lul.html

Click the (+) in the top right to select the "Mapnik" map underlay.

Yes, as @Antje sums it up: it's not just a question of knowing "where", but of locating "where" from legally usable sources. This means either survey + GPS (which doesn't work in tunnels), or textual descriptions, or out-of-copyright materials, or in the longer-term negotiated open data releases under a suitable licence. There are lots of points where the OpenStreetmap tunnel alignment is known to need tweaking and many of these are listed on:

• wiki.openstreetmap.org/wiki/London_Underground#Known_errata

What the errata are waiting for is known-good legally-usable information to make the updates.

The Northern Line CX routeing was not "random" per-se but was drawn carefully from the following textual description received from an (otherwise) reliable source [with whom most of you are familiar with]:
In the absence of anything usable to contradict it, the lines based on this description have been left in-situ and had not been adjusted to a better alignment—it may have been known to be wrong, but somebody needs to publicly say that so that it can be cited as the source.  I have now (23 February 2015) cited the statement on this thread as the source and re-routed the Northern Line Bank Branch up West Hampstead Road; this follows other situations—

• www.openstreetmap.org/way/230065328#map=16/51.5302/-0.1361

Fixing these little bits is where yourself and others could help greatly—one simply needs to suggest textually (ie. without reference to any copyrighted maps!) what precisely needs to be moved where, and they can be fixed quite quickly!

@etr220: Part of goal for independently surveying Tube/shaft locations is not only to get /better/ data, but to show that the information is already widely known in the public knowledge from first principles and daily usage. For example there is another FOI request from somebody else in 2011 that was refused on the basis of the secrecy:

• www.whatdotheyknow.com/request/location_of_mid_tunnel_vent_shaf

By demonstrating that maps already exist, it should dispel the argument that the information is "secret", and then it mainly becomes an issue of delivery format and of licensing. On the licensing front, the Ordnance Survey have last week laid-down their own OS Open Data Licence and switched to standard Open Government Licence, which helps and may help to bring successful negotiation forward.

@rincew1nd: In the Moorgate/Northern City drilling incident the tunnel route was shown on OpenStreetMap, but not on Ordanance Survey or other maps. TfL stated that whilst TfL didn't have a tunnel in the area (the tunnel had been transferred...) but that the conveyancing solicitor would need to contact Network Rail (which didn't happen).

@longhedge: Yes, I have used the RAIB report on the Old Street incident as example of where making usable data widely available actively contributes to public safety, rather than endangering it. The first recommendation from the Rail Accident Investigation Branch (on page 36) is that:
This may/may not have contributed to the TfL "Public Access Property Asset Register" finally being put online. I shall try not to taint myself too much, but I did spot that the location of PiccEx Junction (north-west) of Heathrow Central is shown outside the "LUL Zone of Influence"—and once you've spotted one error in a map it stops being completely trustworthy anyway. …Which is why OpenStreetMap is mapped "from scratch"!

@murph9000: A better Inertial Measurement Unit (IMU/IMS) [such as found on aircraft] would be an excellent contribution to mapping all sorts of things where GPS isn't reliable.

• Sladen, Paul (July 2013) "Tube to Chunnel: Underground mapping" (video, 20 minutes)
  

I did this "Tube to Chunnel" talk a couple of years ago, much of which covers an overview of London Underground mapping in respect of OpenStreetMap, in which I noted out-of-copyright deposited plans weren't always accurate and encouraging validation with IMU/gyro systems. By example, the corner Wood Lane to Uxbridge Road is currently mapped on OSM per the parliamentary deposited plans, however AFAIK the limits of deviation were used to their maximum extent after negotiation and a more gentle curve taken after the present-day location of the control centre.

@phillw48: If the 1944 tunnel map of London is Crown Copyright (term of 50 years), this map would now be out-of-copyright and so it would be excellent to scan and contribute as source material; particular the Post Office railway which could do with some significant refining.  Please do scan and upload somewhere, including any markings in the margins to validate its publication date and origin.

For the sub-surface The c.1897 OS 1:1,056 NLS scans should provide a clean source for refining the sub-surface lines (particularly Mark Lane/Tower Hill/Crescent and the area under Barbican) eg. maps.nls.uk/geo/explore/#zoom=18&lat=51.50996&lon=-0.07753&layers=163

@crusty54: Crossrail are another organisation where it's been hard in communicating to convey the difference between an item being in the public knowledge and being legally usable (out-of-copyright/public domain/explicit reuse allowed. I had put in FOI request to try and obtain the GIS data explicitly under the Open Government Licence for OSM use—it is of course already available from a public Crossrail WMS server, but under unclear terms:

• www.whatdotheyknow.com/request/open_data_crossrail_route_shapef

(We can try again when the tunnels have broken-through as, by having relied on Section 22 (future publication), Crossrail have also committed to publication at some point).

In the middle of the timeline are the Victoria/Jubilee/JLE which are too recent for out-of-copyright map sources and so OGL-licensed open data centre-lines from TfL would be a good solution.

@theblackferret: The you've found appears to be just Bézier curves joining dots, see for example the Bakerloo and Northern line being the wrong way around between Embankment and Lambeth North.

So to return to @norbitonflyer's original starting point: The deposited plans are not geographically precise; TfL's published plans are not totally precise; the current Ordnance Survey plans are incomplete; Metro Carto isn't perfect (I've sent in corrections); the Google Maps tunnel routes are nowhere near accurate; pretty much every non-OSM "geographical map" I've seen is wrong: and can be eliminated with quick checks for South Ken Bends, Embankment?North Lambeth, Claxton Curve, E&C overrun, Paddington Bakerloo and Baker Street Jubilee arrangements.

…Yes, the OpenStreetMap centre-lines are not perfect either (yet), but they can be slowly refined and improved, and are probably the most accurate "legally reusable" ones available.  Plus, improving the station and tunnel mapping is something that we (all, collectively) could actively get involved with, either by mapping or by going out with a pen-and-paper, or collecting numbers/distances only (such as VP numbers—eg. the shafts at Henley's Roundabout and Whitfield Place so they can be added), or merely textually describing known errors and actual route corrections based on first-hand knowledge.

Having the map at the end to point to during discussion will be immensely rewarding, and useful in these conversations!