> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/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/os-downloads/~/changes/AJZwzCsyrD9hiTbOxIbO/topography/os-mastermap-sites-layer.md).

# OS MasterMap Sites Layer

{% embed url="<https://www.ordnancesurvey.co.uk/products/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, and more. The points of access and routing points, to navigate in and out of the sites, are also provided.

{% hint style="info" %}
**This product is updated every six months in April and October.**
{% endhint %}

<figure><img src="/files/gtrmFgi5NUkt0wDADwzG" alt="A representation of OS MasterMap Sites Layer data showing a site area on a map. "><figcaption><p>A representation of OS MasterMap Sites Layer data.</p></figcaption></figure>

OS MasterMap Sites Layer shows what people see in the real world, where the common view of something (such as a school) is not the address, the main building or the playing fields, but is the site as a whole.

{% tabs %}
{% tab title="Features" %}

#### **Accurate risk analysis**

OS MasterMap Sites Layer gives you an understanding of the wider geographic perspective, such as how assets interact with specific types of sites (for example, schools).

#### **Find relevant access points**

Identify where the most appropriate access points into a site are, enabling more detailed planning for emergency situations.

#### **Enhanced analytics**

OS MasterMap Sites Layer routing points enable more efficient responses and more effective deployment of resources.

#### **Seven different themes**

The OS MasterMap Sites Layer groups features into seven themes: Air transport, Education, Medical care, Rail transport, Road transport, Water transport, and Utility or industrial. Each feature is available as three feature types: Functional Site, Access Point and Routing Point.

#### **Solve challenges**

OS MasterMap Sites Layer can help you answer questions like ‘How close is this school to something?’ or ‘What would be affected in the event of an emergency?’.
{% endtab %}

{% tab title="Summary" %}

* **Access:** Download
* **Data theme:** Land Use
* **Data structure:** Vector – Polygons
* **Coverage:** Great Britain
* **Scale:** 1:1 250 to 1:10 000
* **Format:** GeoPackage, vector tiles, GML 3.2.1
* **Ordering area:** All of Great Britain or customisable area (5km² tiles)
* **Publication months:** April, October
* **OS Data Hub plan:** Premium Plan, Public Sector Plan
  {% endtab %}

{% tab title="Guides" %}
We recommend you read the following guides:

* [Getting Started with GeoPackage](/os-downloads/~/changes/AJZwzCsyrD9hiTbOxIbO/getting-started/getting-started-with-geopackage.md)
* [Getting Started with Vector Tiles](/os-downloads/~/changes/AJZwzCsyrD9hiTbOxIbO/getting-started/getting-started-with-vector-tiles.md)
  {% endtab %}
  {% endtabs %}

## How to get this product

Access to this product is free for Public Sector Geospatial (Agreement) PSGA Members. Find out if you are a PSGA Member or find other ways to access OS MasterMap Sites Layer data by visiting the [OS MasterMap Sites Layer product page on the OS website](https://www.ordnancesurvey.co.uk/products/os-mastermap-sites-layer#get), which has links to all of the relevant resources.

## Visualise OS MasterMap Sites Layer data online

This product is available to try out online using one of our three sets of sample data (Exeter, Newport and Inverness) through the OS MasterMap Product Viewer:

<table data-view="cards" data-full-width="false"><thead><tr><th></th><th></th><th data-hidden></th><th data-hidden data-card-cover data-type="files"></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><strong>OS MasterMap Product Viewer</strong></td><td>Interactive demonstrator of <mark style="color:purple;">OS MasterMap Generation</mark> data</td><td></td><td><a href="/files/13IfDwH5Bbrf5BdDSFDn">/files/13IfDwH5Bbrf5BdDSFDn</a></td><td><a href="https://experience.arcgis.com/experience/20981dabcb14402687dccb437a4a78fb/">https://experience.arcgis.com/experience/20981dabcb14402687dccb437a4a78fb/</a></td></tr></tbody></table>

## Other ways to access this data

OS MasterMap Sites Layer data is available through our [OS Features API](https://docs.os.uk/os-apis/accessing-os-apis/os-features-api), providing location-based insights combining topography data with buildings, transport, and water layer data to create finely detailed datasets with a high degree of accuracy. Find out more about our [OS API platform here](https://docs.os.uk/os-apis) to unlock access to rich geospatial data and integrate OS data and services into your applications.

Access to OS MasterMap Sites Layer data is also available through the [OS NGD Land Theme](https://docs.os.uk/osngd/data-structure/land) and [OS NGD Land Use Theme](https://docs.os.uk/osngd/data-structure/land-use), providing data that is interoperable with other OS NGD themes, improved data structures, and a data schema designed to be simple to use and interrogate. Users may find NGD Land Theme data and NGD Land Use Theme data more accessible and easier to use with databases and GIS software. Find out more about [NGD data here](https://docs.os.uk/osngd) to discover how to access OS NGD and what's available to users.

## What's next?

To access additional documentation and resources relating to this product, please refer to the following:

<table data-view="cards"><thead><tr><th></th><th></th><th></th><th data-hidden data-card-cover data-type="files"></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><h2>Overview</h2></td><td>The overview introduces OS MasterMap Sites Layer and gives context for all users – highlighting key features, providing examples of uses, and listing details such as file sizes, supply formats, etc.</td><td></td><td><a href="/files/gl259Tik8hLXgsLnFw8B">/files/gl259Tik8hLXgsLnFw8B</a></td><td><a href="/pages/rISVA3OeS7QFeZPaw4VR">/pages/rISVA3OeS7QFeZPaw4VR</a></td></tr><tr><td><h2>Getting Started Guide</h2></td><td>The getting started guide provides instructions for using OS MasterMap Sites Layer in different software applications. Users with limited technical knowledge will be able to follow this guide.</td><td></td><td><a href="/files/jqT3BGtfUVGmNGebOXjM">/files/jqT3BGtfUVGmNGebOXjM</a></td><td><a href="/pages/NXvgZcTjywGCnqvAYwnC">/pages/NXvgZcTjywGCnqvAYwnC</a></td></tr><tr><td><h2>Technical Specification</h2></td><td>The technical specification provides detailed technical information about OS MasterMap Sites Layer . It is targeted at technical users and software developers.</td><td></td><td><a href="/files/P8ZuFHPc52RpnDlqln9g">/files/P8ZuFHPc52RpnDlqln9g</a></td><td><a href="/pages/38KnzfNeO0uc9SnKCOWt">/pages/38KnzfNeO0uc9SnKCOWt</a></td></tr><tr><td><h2>Downloads</h2></td><td>The downloads page provides links and resources to support the application of OS MasterMap Sites Layer within your environment.</td><td></td><td></td><td><a href="/pages/KN4jsKt5E50i1cDZXcu0">/pages/KN4jsKt5E50i1cDZXcu0</a></td></tr></tbody></table>

{% hint style="info" %}
New users should start with the Overview to gain high-level insight into the product. The Getting Started Guide will help you to begin using product data in different software systems. The Technical Specification contains detailed technical insights.
{% endhint %}


---

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