[Talk-GB] railway stations (again)

[Peter Miller]

Andy Allan made a post recently about former railway stations being tagged
as railway=station and the problems that it causes. I have been reviewing
railways in London and have come across various other instances of multiple
station and various other problems with stations when one starts getting
into higher levels of detail. For example:

Baker Street. There are three separate nodes tagged
'railway=station,name=Baker Street' (one for each line served). In reality
there five separate lines each of which may have 2 platforms (unless any of
them share platforms) together with 4 entrances but only one 'station'.

Embankment. There is a single 'railway-station' node on one of the lines
that stop at Embankment. In reality there are four lines each of which may
have 2 platforms (except for those that share lines) and two entrances.

Westminster. There is a single 'railway=station' node at a crossing of the
two lines. In reality the lines probably cross each other on different
layers and each probably have two platforms. There are a total of 5
entrances according the NaPTAN.

And then there are the mainline stations which in general are more complex.
Here are as sample:

Kings Cross/St Pancras. There is one 'Kings Cross St Pancras', two off 'St
Pancras' and two off 'Kings Cross'. There are areas tagged 'railway=station'
for both Kings Cross and Paddington. Do we need a hierarchy of stations, of
so what would be appropriate?

London Waterloo. There is a single station marked 'London Waterloo'.
However.. the Northern Line was dragged well off its correct alignment to
pass through this node. I have now corrected the alignment but the line is
now not explicitly associated with the station. Should the underground
station be considered as part of the mainline station or not?

Marylebone has three 'stations'. Probably two or one would be better.

Paddington. There are two stations marked as 'Paddington' and one marked
'London Paddington'. The first two are tube stations, the last is the main
line. Should there only be two?

Regarding railway stations as areas. I have found that it is often unhelpful
to tag complex station using an area (railway=station;area=yes) because the
extent of the station often doesn't conform in area to the neat building
outline on the surface - take Liverpool St station as an example where the
extent underground is much further than the visible surface presence.

There is also a recently proposal to clean-up public transport tagging which
received a lot of support (83 approvals against 6 oppositions). We might be
able to use this as guidance for a tagging review in London:
http://wiki.openstreetmap.org/wiki/Proposed_features/Public_Transport

Anyone fancy working on a solution that works when stations are modeled down
to the platform level and which avoids having multiple instances of a single
stations while retaining the correct alignment for the tracks? Incidentally,
we have a view for railway stations on ITO Map here. If shows railway lines,
platforms and connecting passages/stairs/escalators.
http://www.itoworld.com/product/data/ito_map/main?view=79

Regards,


Peter Miller (PeterIto)
ITO World
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