OS Open Roads Lookup Table

OS Open Roads is part of Ordnance Survey’s OpenData product portfolio and is a structured road network which has been generalised to 1:15 000 scale. The OS Open Roads Lookup Table provides the ID of the OS MasterMap Highways Network Road Link feature and the ID of the feature which represents the same feature in the OS Open Roads product which could be either a Road Link or a Road Node. The lookup table will enable a customer to share information they have calculated and pinned to the OS MasterMap Highways Network easily through the OS Open Roads product. Not all Road Link IDs from OS MasterMap Highways Network are included in the lookup table, particularly where the Road Links are shorter than 20m.

The lookup table has been provided as a comma-separated value (.csv) file so the attributes are separated by a comma. Each row will be terminated by Carriage Return / Line Feed, and where an attribute has no value in a record, two commas will be placed together in the record (one for the end of the previous attribute and one for the end of the null attribute). The file will be supplied with headers, and the information is detailed in the sub-sections below.

The CSV file containing the lookup table will be supplied with all orders of OS MasterMap Highways Network – Roads or OS MasterMap Highways Network – RAMI and will be a national set, including with area of interest (AOI) orders. The lookup table is updated every six months, aligned to when OS Open Roads is released. During this period, some of the OS MasterMap Highways Network Road Link IDs could change, be removed from the product or have new IDs inserted which will not be represented in the lookup table because the OS Open Roads product has not been updated to reflect this change. The version of OS MasterMap Highways Network with which the OS Open Roads lookup table is aligned can be identified in the file name.

The file is named OSOpenRoadLookUpTable_YYYY_MM.csv, where YYYY is the four-digit year and MM is the two-digit month (for example, OSOpenRoadLookUpTable_2017_09.csv).

Headers included in the CSV file

Constraints:

• When OSOpenRoads_RoadLinkIdentifier is null, OSOpenRoads_RoadNodeIdentifier cannot be null.

• When OSOpenRoads_RoadNodeIdentifier is null, OSOpenRoads_RoadLinkIdentifier cannot be null.

RoadLink_ID attribute

The ID of the OS MasterMap Highways Network Road Link feature being represented in OS Open Roads.

• Size: 20

• Multiplicity: [1]

OSOpenRoads_RoadLinkIdentifier attribute

The Road Link identifier in OS Open Roads that the Highways feature has been generalised to.

• Size: 38

• Multiplicity: [0..1]

OSOpenRoads_RoadNodeIdentifier attribute

The Road Node identifier in OS Open Roads which the Highways feature has been generalised to (for example, a collapsed roundabout).

• Size: 38

• Multiplicity: [0..1]