Conversion of Symbols from OS Data

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The following is a list of suggested tags for symbols shown on old OS mapping such as the New Popular Edition mapping, (available as a background layer in JOSM and Potlatch)

The advice given below is also generally applicable to Seventh Series maps.


Points of Interest

Notes on conversion of specfic datatypes

Placenames

Use place=* as appropriate - Be careful about changes in local naming though. For Named farms -> use place=farm as a node on the center and landuse=farmyard for the farmyard area if identfiable.

Highways

Roads marked on NPE, can be mapped through appropriate use of highway=*. Typically Trunk routes map to the trunk, other A roads to primary and B roads to secondary tags respectively.

In terms of tertiary roads (i.e non B roads) and unclassified minor roads there is ongoing discussion on how to tag these. Although highway=road exists, it should be used as a last resort, not a catch-all.

Be careful about numbering the Roads from older maps (like NPE).

Footpaths and tracks

DO NOT trace footpaths and minor tracks from old maps, because:

  • In respect of the NPE maps the rights of way shown are not defintive.
  • Footpaths and minor tracks can vary considerably over the 60-70 years since the survey on which these are based was undertaken. (in some cases longer)


Paths marked on NPE, can be tagged as highway=footway, highway=bridleway,highway=path, highway=track, but in many cases direct ground survey of the current situation is strongly recomended.

Railways

For railways and stations that are still active use railway=* as appropriate.

Generally appropriate conversions for railway infrastructure

Former rail infrastructure

For the line/route of disused railways, use railway=disused (tracks still exist albeit overgrown) or railway=abandoned(tracks lifted) as appropriate. railway=abandoned will render at zoom14-18 in mapnik

To record previous railway usage, tag as railway:historic=* alongside current use.


For disused/closed stations use railway:historic=station or railway:historic=station_site unless you can confirm that the station is STILL extant in terms of buildings on the ground. railway=station in combination with disused=yes will also render in mapnik.

You may also want to consider using Lifecycle tags as appropriate. Although not yet rendered disused:railway=station, abandonded:railway=station_site should be considered, longer term.

Former signal boxes can be recorded as disused:railway=box along-side current use, or abandoned:railway=box

Waterways

In general waterways shown on NPE can be mapped to items covered by the waterway=* tag.

In terms of waterways, which since NPE have become disused or abandoned, the following is recommended. (It should be noted however that a 'disused' waterway such as a canal may not necessarily be impassable or unnavigable, although attempts at navigation are not encouraged.)

  • Canals and waterways no longer in use for boats, but mostly intact and 'wet'- waterway=* as appropriate, with additional tags indicating disused status and lack of access.
  • Canals and waterways no longer in use for boats, largely 'dry' or merely 'damp' and substantially impassable, waterway=abandoned.

Waterway:historic=* can also be used to record past waterway use, provided there is evidence of the former use still extant (confirmed bu survey.)

On new efforts (preferably confirmed by survey), Lifecycle prefix should in most cases be used.


Bridges, tunnels, cuttings and embankments

Both Bridges and Tunnels on highways, waterways and railways can be mapped using tunnel=* or bridge=* appropriately on the linear feature concerned.

Cuttings and embankments can in a similar vien be recorded with cutting=* or embankment=*.

There is currently a discussion under way concerning causeways, and on cuttings with respect to minor tracks and paths.

Land useage

Although these conversions are given, it is generally advised to use more recent aerial photography (such as Bing), or ground survey to determine the most recent land use.


Land parcel boundaries

DO NOT MAP from Old OS.

Land 'parcelling' in the UK is complex, and as such the exact parcelling of land shown on the OS map only reflects the situation as shown at the date of the map concerned. Mapping land parcels is better done by reference to more recent sources (OS Opendata) or to arieal photos (Bing).

Administrative boundaries

DO NOT MAP from Old OS.

There are have been at least 3 major restructurings (and plenty of minor boudnary changes) of Local Government since the production of the maps concerned, and the availability of current OS OpenData Boundary Line data, makes mapping of boundaries from older maps redundant.