> For the complete documentation index, see [llms.txt](https://docs.os.uk/more-than-maps/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/more-than-maps/data-demonstrators/topography-demonstrators/os-mastermap-r-demonstrators/os-mastermap-sites-layer.md).

# OS MasterMap Sites Layer

A lightning talk

## Overview of OS MasterMap Sites Layer

OS MasterMap Sites Layer provides a nationally maintained view of the detailed extents of important locations such as airports, schools, hospitals, utility and infrastructure sites. OS MasterMap Sites Layer features are a representation of what people see in the real world, where the common view of something is not the address (such as a school), the main building or the playing fields, but is the site as a whole. The points of access are also provided which can be used to navigate in and out of the sites.

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FEG32Jw7yDhY74wGbtvrM%2FOSMMSites_ProductTree.png?alt=media&amp;token=732106ac-e86d-4252-99d4-06db82ab16b5" alt="Diagram showing the OS MasterMap Sites Layer in the context of the OS MasterMap family of products. It shows the product family including Topography Layer, Water Network, Sites Layer, Greenspace Layer and Highways Network"><figcaption><p>OS MasterMap family of products structure</p></figcaption></figure>

### Where do the features come from?

The features are derived from Ordnance Survey’s detailed data content; the classification and grouping of features is dependent upon the source data's capture specification. This is the same source data that is used in the creation of OS MasterMap Topography Layer and has information about its function or purpose. The Sites Layer is intended to enhance analytical use of this information.

### Themes

The OS MasterMap Sites Layer groups features into seven themes each having both a functional site and at least one access point.

These themes are:

* Air transport
* Education
* Medical care
* Rail transport
* Road transport
* Water transport
* Utility or Industrial.

### Key Characteristics

OS MasterMap Sites Layer represents real-world sites made up of multiple features from OS MasterMap Topography Layer. It enables users to see and create routes to sites such as schools or hospitals as the product also shows the access points to these sites.

The inclusion of access points in OSMM Sites Layer makes it very useful for use in emergency planning. During an incident it is useful to know the location and extent of specific features such as schools, and medical sites and how they are accessed. This can aid the creation of exclusion zones and evacuation plans as the site extent can be taken into account including the access and the type of access to sites.

## Product Details

OS MasterMap Sites Layer contains two feature types.

* Functional site polygons
* Functional site access points

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FrrOrGAqXVrHT3w6wymUB%2FOSMMSites_ProdDetails.png?alt=media&amp;token=75e55186-96ba-4175-ad1e-d6a851e870f0" alt="OS MasterMap sites layer showing functional sites polygons, colour coded by type, and access points, colour coded by access type."><figcaption><p>OS MasterMap Sites Layer showing both functional sites and access points. Red points are Motor Vehicle access, blue points are Motor Vehicle and Pedestrian access, and yellow points are Pedestrian access only.</p></figcaption></figure>

### Functional Sites

Functional Sites are made up of a polygon (object) representing the area, or extent, of the function or activity, with appropriate attribution. It gives information surrounding the functional theme of the site (for example, education), specific site function (for example, primary education), site name, site size, Unique Property Reference Number (UPRN) and additional supporting attribution (for example, version date). It also includes whether the site is operational or not and all the buildings and land within the site.

Including the primary UPRN of the site enables linking of the site to our address suite of products. The product makes it easy to see the area of a site, for example a school, or a hospital, covers.

&#x20;*(Unique Property Reference Numbers (UPRNs) are unique numeric identifiers for every spatial address in Great Britain as assigned by Local Government address custodians.)*

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FgZuA5oE9e34T8GgROklU%2FOSMMSites_FunctionalSites.png?alt=media&amp;token=9783262b-87a3-4e0e-b34c-b3ef3301fd56" alt="Image of OS MasterMap Sites colour coded by type with a legend on the left. Air Transport sites appear in grey, education sites in orange, medical care sites in pink, rail transport sites in purple, road transport sites in yellow, utility or industrial sites in green and water transport sites in blue."><figcaption><p>Different types of functional sites in the OS MasterMap Sites Layer</p></figcaption></figure>

### Access Points

An access point is a point feature type that refers to the accepted and maintained locations where pedestrians and/or vehicles can enter or leave a site. It gives information associated with access type (for example, pedestrian), contains attribution that allows interoperability with other feature types (for example, reference to the OSMM Highways Network) and additional supporting attribution (for example, version date).

Access points makes the creation of routes to sites much more accurate. It can be used to help calculate routes to schools, (walking or vehicular) and emergency access to sites.

Access points are captured and maintained from either a visual inspection of OS MasterMap Topography Layer and Imagery Layer or through field survey. Each Access point feature is positioned on the boundary of the functional site. However, there are possible circumstances where access points do not lie on the site boundary. For example, underground access into a site, and these would be captured in either their true position or within a metre of the functional site extent boundary.

Each access point shows the type of access. These are:

* motor vehicles
* motor vehicles and pedestrian
* pedestrian

{% tabs %}
{% tab title="Motor Vehicles" %}

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FETG5k0AxqyRwWMiLAdX8%2FOSMMSites_AccessPoints_MotorVehicles.png?alt=media&amp;token=2a48ddea-15f0-4d6a-b1bc-6a595bc19925" alt="Image of OS MasterMap Sites including access point features which are classified as &#x22;motor vehicles&#x22;. The access points appear as red point features and the sites appears as polygons colour coded by function"><figcaption><p><strong>Motor Vehicle</strong> access points for sites with OS Maps API as a backdrop for context</p></figcaption></figure>
{% endtab %}

{% tab title="Motor Vehicles and Pedestrian" %}

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FB5lBSiSCXZBeUkVm2b6p%2FOSMMSites_AccessPoints_MotorVehicles%26Ped.png?alt=media&amp;token=66a7889e-8b8a-4883-9b59-679bd8fad20f" alt="Image of OS MasterMap Sites including access point features which are classified as &#x22;motor vehicles and pedestrians&#x22;. The access points appear as red point features and the sites appears as polygons colour coded by function"><figcaption><p><strong>Motor Vehicle and Pedestrian</strong> access points for sites with OS Maps API as a backdrop for context</p></figcaption></figure>

These points could be used for active travel planning as they help in multi modal routing by creating links between different transport types, e.g. from road to rail or air transport.
{% endtab %}

{% tab title="Pedestrian" %}

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FTvthqDsKe712qnEYVF96%2FOSMMSites_AccessPoints_Ped.png?alt=media&amp;token=9a27c023-d3a3-4494-947b-d6f3a5a2b8c8" alt="Image of OS MasterMap Sites including access point features which are classified as &#x22;pedestrian&#x22;. The access points appear as red point features and the sites appears as polygons colour coded by function"><figcaption><p><strong>Pedestrian</strong> access points for sites with OS Maps API as a backdrop for context</p></figcaption></figure>

This is useful for creating routes to schools including walking routes or active travel plans. Walking routes to schools can incorporate paths which make safe routes away from roads.
{% endtab %}
{% endtabs %}

### Creating routes to Sites <a href="#r_3q" id="r_3q"></a>

The site access points include a link to the OS MasterMap Highways Network product via the TOID (topographic identifier) as a unique reference, to the Road Node. This can be used to as part of a routing solution using access rather than a site centroid which gives greater accuracy.

In the below example, Access Point in OS MasterMap Sites Layer has the corresponding TOID to the OS MasterMap Highways Network road node which in this case ends in 4832.

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2Fx0DkRcVTVyxRUKWOQpGa%2FOSMMSites_RoutestoSites.png?alt=media&amp;token=24b3bbe7-7cc7-4c6f-bb9c-057fa15228df" alt=""><figcaption></figcaption></figure>

## Themes in OS MasterMap Sites Layer

### Air Transport

This theme includes sites associated with either the movement of passengers and goods by air, or where aircraft take off and land. Examples include airfields, airports and heliports.

The following features are included in the captured extent:

• buildings for the handling of air passengers and goods

• buildings for the storage and maintenance of aircraft

• aircraft landing and taxiing surfaces (man-made or natural)

• site access roads and paths

• structures associated with the operation of the site

• car parks for air passengers

• areas of man-made and natural surface totally surrounded by included areas

• areas of manmade and natural surface abutting included areas along a non-obstructing edge

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FbIer7iNTrRx0YAtLK599%2FOSMMSitres_AirTransport_3.png?alt=media&amp;token=6db34cab-a15d-45dd-b012-d17d966a4423" alt=""><figcaption><p>An individual Air Transport site, London City Airport with example attributes</p></figcaption></figure>

### Education

This theme includes a very broad group of sites with a common high-level primary function of providing education (either state-funded or fee paying).

The types of educational establishments include Further Education, Higher Education, University, Non State Primary or Preparatory School, Non State Secondary School, First School, Infant School and Junior School, Middle School, Primary School, Secondary School and Special needs Education.

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2Fdsxys3NkS8XmyF09DXEN%2FOSMMSites_Education_3.png?alt=media&amp;token=0987c971-5918-4bd3-898e-810f90472678" alt="Example of an Education site in OS MasterMap Sites Layer with an inset box showing attribution. The highlighted feature appears as a red polygon."><figcaption><p>An individual Education site with example attributes</p></figcaption></figure>

The type of education establishment is shown above which in this case is a Primary School. It shows the school is operational and that the name of the school - Drew Primary.

### Medical Care

This theme includes sites that focus on the provision of secondary medical care services. Examples include: hospice, hospital and medical care accommodation.

The following features are included in the captured extent:

• main buildings;

• site-specific service buildings and structures;

• access roads and paths;

• site-specific car parks; and

• areas of man-made and natural surface surrounded by included areas.

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FCWtAPSiIZgBSw0bDRhP9%2FOSMMSites_Medical_3.png?alt=media&amp;token=f27f3375-05f0-49ff-be0a-560589d0e2a7" alt="Example of a Medical Care site in OS MasterMap Sites Layer with an inset box showing attribution. The highlighted feature appears as a red polygon."><figcaption><p>An individual Medical Care site with example attributes</p></figcaption></figure>

A Medical Care Site is shown above, in this case a Hospice. It's functional status shows it to be operational and gives the name of the Hospice as Richard House Children's Hospice.

### Rail Transport

This theme includes sites associated with the movement of passengers and goods by rail.

Examples are: railway stations, vehicular rail terminals and tram stations.

The following features are included in the captured extent:

• station buildings;

• station shelters;

• platform areas;

• access roads and paths;

• station footbridges and associated structures;

• station car parks;

• areas of man-made and natural surface surrounded by included areas;

• areas of man-made and natural surface abutting included areas along a non-obstructing edge.

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FP24cYa8gBCIiZQvL2rtj%2FOSMMSites_Rail_3.png?alt=media&amp;token=ed1b7716-5d58-4c6a-ae93-9443ecd5260f" alt="Example of a Rail Transport site in OS MasterMap Sites Layer with an inset box showing attribution. The highlighted feature appears as a red polygon."><figcaption><p>An individual Rail Transport site with example attributes</p></figcaption></figure>

A Rail Transport site is show above. It shows that the site is a Railway Station and is the Custom House Station for ExCel.

### Road Transport

This theme includes sites associated with the movement of passengers and goods by road.

Examples are: bus stations, coach stations and road user services.

The following features are included in the captured extent:

• bus/coach station buildings (for example, ticket office or waiting room)

• bus/coach station shelters;

• car/bus/coach parking areas;

• buildings for bus/coach storage, maintenance and cleaning;

• access roads and paths;

• areas of man-made and natural surface.

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FgZy9AOJV0Ynud982vDAw%2FOSMMSites_Road_3.png?alt=media&amp;token=8d25bddb-ee25-44c9-ab3e-c7fec5910568" alt="Example of a Road Transport site in OS MasterMap Sites Layer with an inset box showing attribution. The highlighted feature appears as a red polygon."><figcaption><p>An individual Road Transport site with example attributes</p></figcaption></figure>

A Road Transport site is shown above. Attributes include its status (in this case it is operational), the type of site (a Bus Station) and its name, Prince Regent Bus Station.

### Utility or Industrial

This theme includes sites where the following activities take place:

Where energy (that is, electricity, gas or oil) is produced, refined, distributed or stored.

Sties where the principles of chemistry are applied to materials to create different materials on a large scale.

The following features are included in the captured extent:

• internal site access roads and paths;

• buildings and structures associated with the operation of the site;

• areas of man-made and natural surface totally surrounded by included areas;

• areas of man-made and natural surface abutting included areas along a non-obstructing edge;

• for marine oil terminals, related berthing structures physically connected to the site are included.

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FdiNp5N1M1CP501IYMz0f%2FOSMMSites_Utility_3.png?alt=media&amp;token=66add835-4069-4ece-b4b3-949be4b23a0c" alt="Example of a Utility or Industrial site in OS MasterMap Sites Layer with an inset box showing attribution. The highlighted feature appears as a red polygon."><figcaption><p>An individual Utility or Industrial site with example attributes</p></figcaption></figure>

The attribution for Manhattan Wharf is displayed in the above image. The attribution shows the function of the site which is Oil Distribution or Storage and it is operational.

### Water Transport

This theme includes sites that are involved in the transfer of passengers or goods onto vessels for transport across water.

Examples include vehicular ferry and passenger ferry terminals.

The following features are included in the captured extent:

• port buildings (for example, customs office, ticket office, waiting room);

• vehicle parking/waiting areas;

• structures for loading people, vehicles or goods onto vessels;

• access roads and paths; and

• areas of man-made and natural surface surrounded by included areas.

<figure><img src="https://3774974716-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzIfdYInJITdcxaLLMhlD%2Fuploads%2FhIlRo4fXmJBqYRtbn39J%2FOSMMSites_Water_3.png?alt=media&amp;token=da519843-2fb5-4fea-b6cf-1bc9ae62344d" alt="Example of a Water Transport site in OS MasterMap Sites Layer with an inset box showing attribution. The highlighted feature appears as a red polygon."><figcaption><p>An individual Water Transport site with example attributes</p></figcaption></figure>

The above image shows Royal Wharf Pier, Passenger Ferry Terminal.

## Product Supply

### Available Formats

OS MasterMap Sites Layer is supplied in three different formats:

• Geography Markup Language (GML) 3.2.1\*

• GeoPackage

• Vector tiles (MBTiles)

\*Note that the GML version differs from OS MasterMap Topography Layer.

OS MasterMap Sites Layer is made available using a web-based ordering system, [OS Data Hub,](https://osdatahub.os.uk/) which allows customers to order their initial data supply and obtain price estimates as appropriate. When placing an order, customers can view details of their holdings. The product is supplied as an online download.

### File Sizes and Coverage

OS MasterMap Sites Layer is a national dataset and is maintained and supplied as 5km² tiles of data as an Area of Interest (AOI) or as Great Britain (GB) supply.

File size estimates can vary from about 2KB compressed to about 162KB (compressed) for tile supply. A full GB supply will be approximately 43MB compressed. Compression rates vary and are dependent on the size and content of a tile.

For GeoPackage and vector tiles, the coverage will be GB supply only. The file size is approximately 90MB zipped for GeoPackage, and 160MB zipped for vector tiles.

For more information on the GeoPackage and Vector Tiles please see links below to the Getting Started Guides.

* [ OS MasterMap Sites Layer - Getting started with GeoPackage ](https://docs.os.uk/os-downloads/getting-started/getting-started-with-geopackage)
* [ OS MasterMap Sites Layer - Getting started with Vector Tiles ](https://docs.os.uk/os-downloads/getting-started/getting-started-with-vector-tiles)

### Update Schedule

The OS MasterMap Sites Layer is maintained alongside other Ordnance Survey large scale-content in an integrated edit environment. This will ensure that any relevant real-world change is updated in all relevant OS MasterMap Layers at the same time.&#x20;

The OS MasterMap Sites Layer is updated every six months (April and October) as a full supply.

Change-Only Updates (COU) are not available for OS MasterMap Sites Layer.

## Styling

A sample style for the graphical depiction of the functional site extents, and access points has been designed to aid customers with illustrating this product. Ordnance Survey has created Style Layer Descriptors (SLD); these can be found on [GitHub](https://github.com/OrdnanceSurvey/OSMM-Sites-stylesheets).

See [here](https://docs.os.uk/more-than-maps/geographic-data-visualisation/geodataviz-assets/styling-data/how-to-download-and-use-os-stylesheets) for a guide on downloading and using OS style sheets.

## Supporting Documents

* [OS MasterMap Sites Layer - Technical specification](https://docs.os.uk/os-downloads/topography/os-mastermap-sites-layer/os-mastermap-sites-layer-technical-specification) The technical specification provides detailed technical information about the product. It is targeted at technical users and software developers.
* [OS MasterMap Sites Layer - Getting started guide](https://docs.os.uk/os-downloads/topography/os-mastermap-sites-layer/os-mastermap-sites-layer-getting-started-guide)
* [OS MasterMap Sites Layer - Getting started with GeoPackage](https://docs.os.uk/os-downloads/getting-started/getting-started-with-geopackage)
* [OS MasterMap Sites Layer - Getting started with Vector Tiles](https://docs.os.uk/os-downloads/getting-started/getting-started-with-vector-tiles)
* [OS products refresh dates](https://docs.os.uk/os-downloads/resources/product-refresh-dates)

***

Links that may be useful:

{% embed url="<https://osngd.gitbook.io/osngd/>" %}

{% embed url="<https://osdatahub.os.uk/>" %}


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