OS MasterMap Highways Network support

Resources and frequently asked questions to help you make the most of this product.


OSMM Highways Network brings together data from authoritative sources such as the National Street Gazetteer (NSG) and OS Large Scale Road data to create a single authoritative view of the road network.

Current release: April 2019


Learn more about how Highways products work and how you can make the most of them

Watch now

What is OS MasterMap Highways Network?

OSMM Highways Network is our new generation of product for road and path information. It brings together definitive geographic information from OS and data from authoritative sources such as the National Street Gazetteer (NSG) to create a single authoritative view of the road and path network.

It is a topologically structured road and path network which has been heighted and is attributed with associated information including classification, road name(s) and number. Detailed routing information is available, ranging from banned manoeuvres to structures along the road network, which could affect your choice of route, for example traffic calming.

Finally, there's information available to help you understand more about the road or path as an asset, ranging from who the responsible authority is for maintaining it, to designations being assigned such as lane rental schemes and traffic sensitive streets.

Why do we need a new highways product?

There are a large number of roads datasets used across government and other organisations. Using different datasets in different application it is increasingly hard for our customers to answer simple questions like how long is this A-roads? One dataset might say 100km and another 98km but which is right? 

Department for Transport has the same problem and it makes implementing policy hard when your figures can be instantly challenged. By bringing together two of the key datasets that government use, we gives customers  confidence that the decisions they make are based on a single authoritative view of the road network.

Does it cover all of Great Britain?

Yes, the dataset OS has built will use ITN as the base network, so it will have the same coverage as ITN and be fully routable. We have also included authoritative information from local authorities for England and Wales. In Scotland the authoritative information is not available.

Is this in the Public Sector Mapping Agreement?

Highways Data is included in both Public Sector Mapping Agreement and One Scotland Mappring Agreement. Existing customer, PSMA or OSMA member? Log in to order data

For more information, phone 03456 05 05 05.


What are the data sources for OS MasterMap Highways Network?

The data is currently sourced from two sources:

1. OS Large Scale Content
We've provided national coverage of the Road Network and the associated attribution and detailed routing information. This is the same source of information used to create OS MasterMap Integrated Transport Network and therefore covers all of Great Britain.

2. National Street Gazetteer
GeoPlace provides Ordnance Survey with the National Street Gazetteer for England and Wales. The National Street Gazetteer is created through the compiling of 174 Local Street Gazetteers (LSGs) and the Trunk Road Street Gazetteer (TRSG). The TRSG provides the authoritative information about the road and path network.

What is the accuracy of OS MasterMap Highways Network product?

An indication of the positional accuracy is contained in the expected accuracy of the Topographic data from which the road network lines are derived; 0.5m RMSE, 1.1m RMSE or 4.1m RMSE. However, given the nature of a representative alignment and the difficulty in identifying the true position these precise numbers, it should not be used to indicate the accuracy of individual network links.

The alignments are the same as those in OS MasterMap Integrated Transport Network (ITN).

Also in OS MasterMap Highways Network data, the Road Link feature has an attribute called Provenance which tells you the origin and derivation of the three dimensional geometry of the Road Link. You can find more detailed information about this on page 17 of our OS MasterMap Highways Network Road technical specification document (PDF).

The Provenance attribute is populated with values from the ProvenanceSourceValue codelist (page 40 in the spec). The codelist provides information on the source of the three dimensional geometry, which always comes from OS at Road Link level. However it is of different types of accuracies. For example, the OS Urban and OS Height Data value tells you that the data is derived from data captured to 0.5m planimetric accuracy. And elevation is obtained from drape of OS detailed height content which has a resolution of 2m.

How is information about routing and assets represented in this product?

Both routing and asset management information are not applied to the base network, but are using network referencing to be able to relate these features back to the road and path network.

Routing and Asset Management Information has been categorised into the following themes:

  • Rights and Restrictions: Defines properties that restrict, regulate or prohibit the use of the network by traffic which may affect the allowable route for users.
  • Advisory Information: This provides additional information that may affect a driver’s preferred choice of route or highlight potential hazards such as the presence of a toll or level crossing.
  • Asset management information: Provides additional information describing the network, to support its long-term operation and maintenance. This has been sourced from the road or highways authorities and includes: Maintenance, Reinstatement and Special Designation.

The following types of rights and restrictions are in scope in the current product:

  • Access Restrictions
  • Turn Restrictions
  • Restrictions For Vehicles (Height, Weight, Width and Length restrictions)
  • Highways Dedications (indications of Rights of Way)

To whom the restrictions apply and any time constraints are also captured.

Advisory Information features are represented in two categories:

  • Hazards: Locations which are dangerous, and caution should be taken to ensure safe travel. Examples include: Fords and Dangerous Bends.
  • Structures: Are built features which relate to the highway. Examples include Barriers, Bridges and Tunnels.



Are there further product developments planned?

Currently there are no further product development plans for changing the schema to OS MasterMap Highways. However there could potentially be small improvements applied across the product

We've designed OS MasterMap Highways Network in a modular form. This means that if you only want one of the features, you will only need to load the file that holds it. 

There's also an added benefit to this which means that once we've delivered a module, there's no need for us to go back and make changes to that module – each module lives in isolation. This will enable our customers who are producing tools to avoid revisiting work.

What are the main things OS MasterMap Highways Network will do?

OS MasterMap Highways Network will contain a combination of routing information and asset information to meet requirements gathered from the existing customer base. The data will contain all the information that is contained within Integrated Transport Network (ITN), although is packaged differently to meet the changing demands of OS customers over the last 10 years.

Also, the product will contain street information at local highway authority level. The benefit of this is that the data capture is at the earliest point of creation within the local highway authority and there is detailed local knowledge driven by statutory requirements.

Some of the key features of OS MasterMap Highways Network product are:

  • Unique Street Reference Number (USRN)
  • Road names from the naming and numbering authority
  • Department for Transport road classifications
  • Road Maintenance authority
  • Motorway Junction to junction information
  • Routing information
  • Height, weight, width and length restrictions information
  • Special designations
  • Road reinstatement information
  • Connected network across GB including all islands through the Ferry Network.

One of the main benefits of the product is bringing together disparate datasets across government. It gives a single authoritative view of the road and path network that underpins decision making across government and the commercial markets.

What are the schemas required to translate OS MasterMap Highways data?

All schemas required to translate OS MasterMap Highways Network product data (including the Inspire schemas) can be downloaded and used locally from: https://github.com/OrdnanceSurvey/OS-MasterMap-Highways-Network-ALL-Schemas

You can also go to our OS MasterMap Highways schema page.

What's happening to ITN?

From 31 March 2019 our Integrated Transport Network (ITN) product will be withdrawn and replaced by OS MasterMap Highways Network. The last update to ITN will be scheduled for 25 February 2019.

For all the information about the migration including why it's happening; the benefits of Highways; a comparison between ITN and Highways; a timeline of events; webinars and FAQs - please visit our dedicated web page www.os.uk/itnmigration.

What are the steps I need to take when migrating from ITN to Highways?

If you're already using ITN in live systems, the first step would be to have a look at Highways data and to try putting it in your live systems. You can try our Highways sample data for free.

After looking at the Highways data and specification, the next step would be to ask yourself the following questions:

  • What do I want to do with Highways?
  • Can I do a straight swap?
  • What do I do with data I have added to ITN?
  • Does my system support Highways?

To help answer the above questions you need to do a comparison of the two products. Start to think about the features and attribution that you need and do your transition in that way.

All of the features from our Integrated Transport Network product appear in OS MasterMap Highways Network - please see a comparison table and a document detailing this information at www.os.uk/itnmigration.

If you added any data to ITN, this data can be transferred across to Highways as all the TOIDs in OS MasterMap ITN have been carried over into OS MasterMap Highways Network.

We've been working with the Partner community to support their migration to OSMM Highways Network. For a list of OS Partners who are ready for the transition or that have solutions in development, please see www.os.uk/itnmigration. Please let us know if you're using a system we are not aware of, and always check with your system provider if you're unsure or require further information.

We've also put together a migration toolkit which you can find on our dedicated migration web page: www.os.uk/itnmigration. This includes the following support materials:

  • Comparison table between the two products
  • ITN to Highways document – similarities and differences between ITN and Highways
  • FME workbenches - https://github.com/OrdnanceSurvey/OSMM-Highways-Network-Support
  • Migration guide – recipes and use cases to help users getting started
  • Getting Started Guide
  • Local copy of all Highways schemas - https://github.com/OrdnanceSurvey/OS-MasterMap-Highways-Network-ALL-Schemas
  • Webinars - see dedicated migration web page to sign up for future webinars, but also to watch previous webinars. Previous webinars include the following themes: Technical explantion on the OS MasterMap Highways products, What to consider when migrating from ITN to Highways.
What's happening to the National Street Gazetteer (NSG)?

The NSG is used in the statutory coordination of streetworks and will continue to underpin requirements under the New Roads and Streetworks Act (1991) for the foreseeable future.

The Local Street Gazetteer (LSG) and NSG process is vital to the creation and ongoing maintenance of the product and this data combines to form a fundamental component of the OS MasterMap Highways proposition. The long term aim is that OS MasterMap Highways is used as single dataset across public sector operations but there is no immediate plan to withdraw the NSG from the streetworks process as it currently stands.

Discussions will take place about the future of the NSG and this will be undertaken with input from the streetworks community across DfT, local authorities, utilities and their representative organisations. For more information about the NSG please visit www.geoplace.co.uk/streets/managing

Any customer that uses NSG, is also having to license OS MasterMap Highways Network (replacement for ITN) – as part of the T&Cs of the NSG.


How regularly is OS MasterMap Highways Network updated?

OS MasterMap Highways Network is published once a month, on the first working day of every month.

How do I give feedback?

Please get in touch on our forum or contact our Customer Service Centre.