[Tagging] railway=rail vs. railway=subway

Tue Nov 22 22:26:31 UTC 2016

Hi,

railway=* should depend on the infrastructure only. The services which
use the track, don't matter.

Am 22.11.2016 um 15:41 schrieb Michael Tsang:
> On Tuesday 22 November 2016 11:28:00 jc86035 wrote:
>> Should a commuter rail system with rapid transit frequency but main
>> line-standard tracks be tagged as railway=subway or railway=rail?
>>
>> In Hong Kong, the MTR metro system has an "urban" set of DC 1432mm-gauge
>> lines, and another set of AC standard gauge lines (East Rail Line, West
>> Rail Line and Ma On Shan Line) connected to the Guangzhou–Shenzhen railway.
> 
> "Use railway=rail for full sized passenger or freight trains in the standard 
> gauge for the country or state.
> railway=rail is the largest railway classification, for full-blown full-sized 
> railways."
> 
> My interpretation of the above rule is that, if the section of the railway is 
> capable for running long distance trains, it should be tagged as railway=rail. 
> Therefore, East Rail Line in Hong Kong is definitely railway=rail because long 
> distance and freight trains also run on it.

I agree up to here.

> In my opinion, even the metro-only 
> sections of East Rail Line where long distance trains do not run should be 
> tagged as railway=rail because they belongs to the same railway with the same 
> standard.

If the metro-only sections have a wide structure gauge which would
permit long distance and freight trains to use it (tunnels wide instead
of narrow), they should be tagged railway=rail. But if the tracks can
only be used by metro trains, they should be tagged railway=subway.

Metro tunnels are usually more narrow than tunnels for full sized
passenger trains because building wide tunnels is more expensive.

> Normally I consider the nature of the train running on the railway to get the 
> appropriate railway=* value.
> 
> - Railway with long distance and commuter trains: railway=rail
> - Railway with metro services only: railway=subway

railway=subway are usually encapsulated systems which may have a
connecting track if new vehicles are delivered and both systems have the
same gauge. railway=subway systems don't have level crossings.

Finally, you cannot write a fix rules which is suitable for every
country and every city. In some cases you have to make exceptions from
the fixed rules. I think that metro-only tracks in Hong Kong should be
tagged as railway=subway even if they are connected to full-sized
railway tracks.

You can use route=subway for the route relations to indicate that it is
a metro-like service with metro-like vehicles.

> - Railway with street intersection: railway=light_rail
> - Railway mainly with tracks embedded on the street: railway=tram

+1

>> One of the standard gauge lines (Ma On Shan Line: short distance between
>> stations and low speed) was always tagged with railway=subway, but some
>> time ago I retagged the West Rail Line (commuter rail with long distance
>> between stations) with railway=subway, as well as the sections of the
>> East Rail Line without intercity train service (without asking anyone).
>> Should the lines be retagged as railway=rail, since they're not really
>> subway/metro lines?
> 
> For Ma On Shan Line and West Rail Line, there is a bit ambiguity. The trains 
> running on them are full sized passenger trains in the standard gauge, but 
> they are metro trains in all aspects, even all the technical standards are 
> comparable to main line standards. In fact, West Rail Line was planned to have 
> long-distance trains and freight trains at the beginning, if this were to 
> become true, it would be re-tagged as railway=rail. However, the plan was 
> dropped and in the forseeable future only metro services would be run on West 
> Rail Line so I prefer railway=subway in this case. Ma On Shan Line is designed 
> to have only metro service so it is definitely railway=subway, but because it 
> will be connected with West Rail Line so it was built to same full size 
> technical standard.

If the infrastructure can be used by full sized passenger trains, it's
always railway=rail. It's not that strange that light rail services use
railway=rail tracks. Have a look at the light rail line from Karlsruhe
to Hochstetten. It uses railway tracks which are also used by freight
trains between Welschneureuter Straße and Leopoldshafen Frankfurter
Straße (freight trains go to KIT Campus Nord, formerly Karlsruhe
Research Centre).
http://www.openrailwaymap.org/?lang=&lat=49.076789590142965&lon=8.403253555297852&zoom=13&style=standard

> Even the situation of East Rail Line is not completely clear. In 1983, East 
> Rail Line was a relatively infrequent (20-minute headway in outer suburbs) 
> commuter rail service using British national railway standard, comparable to 
> S-Bahns in Germany.

S-Bahns in Germany (those operated by DB) are tagged as railway=rail [1]
because most of them share the tracks with all other types of trains
(freight, regional, high-speed). S-Bahns are normal trains and therefore
their route relations are tagged with route=train. (Normal train tickets
are valid in S-Bahns but not on metros (U-Bahn), trams and light rails
(Stadtbahn))

In Germany, the law helps you to distinguish the different types of
railways. A law called EBO rules the operation on full-sized railway
lines with standard gauge, another law called BOStrab rules everything
else (trams, light rails not running on EBO tracks, subways). Locations
where a vehicle enters a section ruled by the other law are signed.

https://commons.wikimedia.org/wiki/File:Systemwechsel_Stadtbahn_Karlsruhe.jpg

I don't know if there are different laws in Hong Kong for full-sized
trains and subways.

> If OpenStreetMap existed at that time, the train service 
> itself would be tagged as route=train. However, the frequency became metro 
> standard in early 1990s, the trains renewed to metro standard between 1996 to 
> 2000, and joined the metro network in 2007, so it is tagged as route=subway 
> now.

That's right.

> In fact, the boundary between railway=rail, subway, and light_rail is not 
> always clear. There exist some trains in elsewhere in the world which can run 
> on mail line railways (railway=rail), inside metro network (railway=subway), 
> and even on the road waiting red lights with motor vehicles 
> (railway=light_rail).

You are speaking of Germany? Cologne and Bonn share some light rail
lines which use railway tracks (used by freight trains, too) outside the
cities and light rail tracks (sometimes underground but still a light
rail, often called "subway"/"U-Bahn") inside the cities.

Best regards

Michael
(one of the guys behind OpenRailwayMap)

PS Public Transport is difficult. If you think you know everything, you
have not seen all of the world.

[1] except in Berlin and Hamburg where the mappers need to be convinced :-)

-- 
Per E-Mail kommuniziere ich bevorzugt GPG-verschlüsselt. (Mailinglisten
ausgenommen)
I prefer GPG encryption of emails. (does not apply on mailing lists)

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