OS MasterMap Highways Network products' features are classified into feature types. Each feature type has associated attribution, and further detail of this can be found in each product's technical specification.

Core features included in the Roads product

• Road Link

• Road Node

• Road

• Street

• Road Junction

• Ferry Link

• Ferry Node

• Ferry Terminal

Core features included in the RAMI product

• Road Link

• Road Node

• Road

• Street

• Road Junction

• Ferry Link

• Ferry Node

• Ferry Terminal

• Access Restrictions

• Turn Restrictions

• Restrictions For Vehicles

• Hazards

• Structures

• Maintenance

• Reinstatement

• Highways Dedication

• Special Designations

Core features included in the Paths product

• Path Link

• Path Node

• Connecting Link

• Connecting Node

• Path

• Street

• Ferry Link

• Ferry Node

• Ferry Terminal

• Maintenance

• Reinstatement

• Highways Dedication

• Special Designations

Comparison of the feature types included across the three products

The following comparison table details the feature types present within the OS MasterMap Highways Network products. The letter Y indicates that a feature type is present in a product, whereas the letter N indicates that a feature type is not present in a product.

The following pages give a description for each feature type.

A Connecting Node is a point feature which identifies where a Path connects to the Road Network. The Connecting Node connects to the start or end of one or more Road Links and they are spatially coincident with Road Nodes.

A Path Link is a line segment representing the alignment of a path. Path Links hold information about the name of the path, its length and its nature, alongside other attribution which is detailed in the OS MasterMap Highways Network – Paths Technical Specification. Path Links define the geometry and connectivity of the Path Network between two points.

Path Links will be captured where:

• They provide a route that cannot be inferred from the Road Network

• They provide connectivity between road networks

• There is a canal path or tow path

• There are paths over footbridges and under subways

Path Links will not be captured where:

• They run parallel to the Road Network, for example, a pavement

• They are within school boundaries and cemeteries where there are closing times

• They are connected to a motorway

• There is a physical obstruction which prevents connectivity

• There are multiple paths that essentially serve the same purpose when some rationalisation is applied

A Path feature is like a Road feature as it holds information about path names which have been captured by Ordnance Survey. A Path feature is a link set which will reference the Path Links which share the same name, irrespective of which local authority is responsible for it. A Path Link could be referenced by multiple Path features.

A Road Link is a line segment representing the general alignment of the road carriageway. It can represent single carriageways, dual carriageways, slip roads, roundabouts and indicative trajectories across traffic squares. It defines the geometry and connectivity of a road network between two points. Road Links hold information on the road name, classification, form, length and other attributes which are specified in the .

A Path Node is a topological node connecting to at least one Path Link, providing network connectivity. It is a point used to represent connectivity between Path Links or the end of a road.

The Road and Path Network are topologically structured together. Connecting Links enable this connection between the Road Network and the Path Network. A Connecting Link is a line segment which represents a logical connection between the Path Network and the Road Network; it does not represent a real-world feature.

A Rode Node is a topological node connecting to at least one Road Link, providing network connectivity. It is a point used to represent connectivity between Road Links or the end of a road. A Road Node will hold information on its classification, and if it forms a part of a numbered junction, then the Road Node will provide this number.

A Road feature holds information about road names and road numbers which have been captured by Ordnance Survey. A Road feature will reference the Road Links which share the same name (for example, Wellington Road in the image below) or number (for example, the A41 in the lower image), irrespective of which local authority is responsible for it. The link set may not be contiguous across junctions or where a road consists of separate sections, which may be separated by some considerable distance. A Road Link could be referenced by multiple Road features.

The road and path networks are connected to the ferry network through the Ferry Terminal feature, which acts as a network connection feature. The Ferry Terminal is a logical connection and therefore no geometry is supplied. In addition to connecting the networks together, the Ferry Terminal feature will also provide the terminal name and the three-letter NaPTAN code used by the Government to identify terminals uniquely.

The Street feature is the definition of the Street as defined in the National or Scottish Street Gazetteer. Local authorities have a statutory responsibility which means that they are the source of information for both street naming and managing the highways / roads network.

Each Street feature has a USRN (Unique Street Reference Number), a unique and persistent identifier for a street contained in either the National or Scottish Street Gazetteer. Every street, road, track, path, cycle track or way is assigned a USRN by a Roads Authority, Local Highway Authority or Highways England. Each authority is provided a USRN range that is centrally allocated and managed by GeoPlace in England and Wales and by Improvement Service in Scotland.

A Street feature encompasses both Roads and Paths. Therefore, a Street feature will reference the Road Links or Path Links. Where a Street crosses an administrative boundary, a new Street feature will be created. A Road Link or Path Link could be referenced by multiple Street features.

The Street features which are supplied with the RAMI product will contain all Street features which have either been matched to at least one Road Link or have not been matched. The Street features which are supplied with the Paths product will only contain Street features which have only been matched to a Path Link.

A Ferry Link is a line segment that connects the road network and path networks across bodies of water. The link can represent the route a ferry may take between terminals; otherwise, the link will be a straight line between two terminals. In addition to connectivity information, a Ferry Link also provides data on who operates the service and if the service is limited to pedestrians. A Ferry Link will only be captured where both terminals are within Great Britain and where there is a timetabled service available to the public.

A Road Junction holds information about junction names and numbers. The feature will reference all the Road Nodes which correspond to the junction the feature is representing. Multiple Road Junction features could reference a Road Node. In the current release, the Road Junction feature will only identify Numbered Motorway Junctions.

A Ferry Node is a point feature which identifies where the Ferry Network terminates. They will always be referenced by at least one Ferry Link.

An Access Restriction is a feature where access to a road or area by vehicles can be legally prohibited. Prohibited access restrictions are indicated by regulatory signs with a red circle or a no entry sign. In addition, access could be limited for use by particular classes of vehicle; these are indicated by regulatory signs with a blue circle. Access restrictions may also include exemptions to the restriction. The Access Restriction Feature Type comprises these types of restrictions.

Maintenance provides information about whether a Path is maintained at public expense by a national or local highway authority, by a road authority or is maintained by another responsible organisation (i.e. not maintained at public expense). If a Path is prospectively maintainable at public expense, then this is not currently maintained by a road or highway authority, but the responsible organisation has started the process for a highway or road authority to become responsible for the maintenance of the Street at public expense.

Hazards are locations which are hazardous and where caution should be taken to ensure safe travel. Hazards are usually signed using a warning sign. Hazards include Fords and Dangerous Bends.

A Turn Restriction is a restriction based upon a vehicle manoeuvre. The types of restriction include a prohibitive driving instruction, a mandatory driving instruction and implicit restrictions. Prohibited instructions are indicated by road signs within a red circle, and examples include No U-turns, No Right Turn and No Left Turn. These can include exceptions to the instruction and are typically elements like Except for Buses. Mandatory driving instructions are indicated by road signs within a blue circle or are painted on the roadway, and examples include Turn Right and Ahead Only. Implicit restrictions occur where a turn is not signed as prohibited but would not be a normal manoeuvre, for example, where a road splits around a traffic island or at complex junctions where additional geometry has been captured to reflect the traffic flow. These are not differentiated from actual signed restrictions.

Reinstatement defines the standard to which the highway must be restored to following opening due to works in the highway, as defined in the New Roads and Street Works Act Specification for the Reinstatement of Openings in Highways in England and Walesand the New Roads and Street Works Act 1991 Specification for the Reinstatement of Openings in Roads in Scotland.

Restrictions For Vehicles are restrictions that apply to the physical characteristics of vehicles. These are required to protect structures such as bridges and tunnels from damage, or to restrict / prohibit use by vehicles that exceed dimensions, usually for physical reasons. In addition, Restrictions For Vehicles includes exemption to the restriction when specific use conditions apply (for example, loading and unloading). The restrictions include:

• Maximum Height

• Maximum Width

• Maximum Length

• Maximum Weight

Height, width, length and weight restrictions may be defined using either regulatory signs or warning signs. By default, the restriction is always provided in the metric unit, and the imperial measure will be provided where it is signed.

Highway Dedications provide an indication of the type of user who has access to that particular section of the Highway. Highway Dedications may reference public rights of way but are not a definitive record of such.

Every section of geometry supplied by a local highway authority will have a type of dedication associated, in line with the Highways Act 1980 and the Countryside and Rights of Way Act 2000, which determine the highway user access.

Special Designations are statutory and advisory designations that can be applied to protect a highway when street works are to be undertaken. Special Designations exist to reduce the bureaucracy involved in managing street works, with an emphasis on minimising delay and inconvenience to road users, whilst protecting the integrity of the street and any apparatus on it.

Structures are the location of key built features that relate to the highway network. The types of features provided include bridges; barriers which can control, obstruct or prevent passage or access; tunnels, and equipment which would control the flow of traffic.