A code list is a controlled set of values for a free text data type which can be extended. This section identifies the code lists used within OS Open Roads and describes their values.
Classification of roads exists to ensure that there is a feasible, logical road network throughout the country. Road classifications should be set to take into account the traffic management goals and road categorisation approach of the local highway authority (LHA).
The RoadLink feature is attributed with a roadClassification with a data type of RoadClassificationValue. The following table lists the codes which are used populate this field and gives a description for each code.
| Code | Description |
|---|---|
Motorway
A multi-carriageway public road connecting important cities.
A Road
A major road intended to provide large-scale transport links within or between areas.
B Road
A road intended to connect different areas and to feed traffic between A roads and smaller roads on the network.
Minor Road
A public road that provides interconnectivity to higher-classified roads or leads to a point of interest.
Local Road
A public road that provides access to land and/or houses, usually named with addresses. Generally, not intended for through traffic.
Local Access Road
A road intended for the start or end of a journey; it is not intended for through traffic but will be openly accessible.
Restricted Local Access Road
A road intended for the start or end of a journey; it is not intended for through traffic and will have a restriction on who can use it.
Secondary Access Road
A road that provides alternate/secondary access to property or land; it is not intended for through traffic.
Motorway
A multi-carriageway public road connecting important cities, classified by the Department for Transport. A Motorway does not form part of the official road classification scheme as it is a Special Road. However, it has been included to allow them to be classified.
A Road
A major road intended to provide large-scale transport links within or between areas.
B Road
A road intended to connect different areas and to feed traffic between A roads and smaller roads on the network.
Classified Unnumbered
Smaller roads intended to connect unclassified roads with A and B roads; often linking a housing estate or a village to the rest of the network.
Note 1: These were ‘minor roads’ in ITN (retired OS product) and are sometimes known unofficially as C roads.
Note 2: A Street may be assigned a local classification number by the local highways authority.
Unclassified
Roads intended for local traffic.
Note 1: The vast majority (60%) of roads in the UK fall within this category.
Note 2: These may be designed unofficial local road classifications, for example, D, E, F and G roads.
Not Classified
Roads that have not been assigned a road classification at national or local level by a designation authority.
Unknown
The classification of the road is unknown because the RoadLink is not a Motorway, A or B road, and the RoadLink has not been matched to any other road classification at national or local level.
The RoadNode feature is attributed with a RoadNodeCategory with a data type of TransportNodeTypeValue. The following table lists the codes which are used to populate this field and gives a description for each code.
This code list is inherited from INSPIRE and is not extendable.
Functions of road nodes within Euroroads.
http://inspire.ec.europa.eu/codelist/FormOfRoadNodeValue
| Code | Description |
|---|---|
junction
Road node where three or more road links connect.
pseudo node
Exactly two road links connect to the road node.
road end
Only one road link connects to the road node. It signifies the end of a road.
roundabout
The road node represents or is a part of a roundabout.
Single Carriageway
A road consisting of one carriageway with traffic in one or both directions. There may be more than one lane in either direction.
Dual Carriageway
A road consisting of two separate carriageways with separate flow directions. The carriageways are partitioned by physical features, such as a barrier and/or verge.
Slip Road
A link that provides exit from or entry to another link.
Roundabout
A method of controlling traffic flow by allowing vehicles from a particular direction priority.
Collapsed Dual Carriageway
The geometry of the dual carriageway has collapsed; this occurs where they run parallel and are less than a defined distance apart, resulting in a single line representing both carriageways of a dual carriageway.
Guided Busway
A specially-constructed or modified route for passenger road vehicles that have been built or adapted to be steered by external means. Typically, along guided busways there is a raised kerb with a track along which small wheels protruding from the sides of the modified vehicle run. This classification is only for specific cases where buses run along specifically-designed tracks or channels that remove the need for steering.
Shared Use Carriageway
Roads that have been altered for use principally by pedestrians, but may also provide some access for certain types of vehicles.
Road In Tunnel
A road that passes underground or under water.
Road On Bridge
A road that passes over a river, railway, road, or ravine on a structure.
Note: This value is currently not populated.