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Using OS MasterMap® Topography Layer in QGIS

This page is intended to allow users to quickly get started using OS MasterMap Topography Layer data in QGIS.

QGIS is a fully featured Free and Open Source desktop GIS package. Here we’ll describe how to load, view and apply styles to the Topography Layer


You’ll need the following before starting:

  • A working copy of QGIS 1.5 or later (if you haven’t yet installed QGIS you can get it from here)
  • An internet connection (for QGIS to download the OS Translator plugin)

See here for further information on how to install and use QGIS.

OS Translator

OS Translator is a plugin intended to help users obtain, style and use Ordnance Survey data in QGIS. The current release of the plugin allows Ordnance Survey MasterMap Topography Layer GML files to be converted to ESRI shapefile. Working with shapefiles in QGIS is easier and faster than working directly with GML. A set of qml (QGIS styling) files and SVG files will be provided for styling Ordnance Survey MasterMap in accordance with Ordnance Survey’s style guidelines.

We hope to add extra functionality (including support for the PostGIS geodatabase) in the near future.

To report an issue or request a new feature, use the project issues page on GitHub or the OSGeo wiki page for Ordnance Survey-related tools.

Installing the OS Translator plugin

Follow this procedure to install the plugin:

  1. Select Fetch Python Plugins… from the Plugins menu.
  2. Python plugin menu

    The QGIS Python Plugin Installer dialog should appear.

  3. Enter translator into the Filter box.
  4. Filtering Plugins for OS Translator

  5. Select the OS Translator entry and click Install plugin.
  6. Click Close.

If you have any problems, see the Troubleshooting section for some possible solutions.

Using OS Translator

The following instructions will demonstrate how to convert Ordnance Survey’s MasterMap Topography sample data into Shapefiles which can be opened in QGIS.

Ordnance Survey Translator Plugin
  1. Open QGIS and click on the OS Translator button OS Translator Tool in the Plugins toolbar.
  2. Set Folder Containing Input Files to the location containing your .gz files. Input files can exist in sub-folders of the given location. If more than one .gz file is found under the specified folder and its sub-folders all .gz files are converted.
  3. Folder For Outputs specifies where output files will be written.
  4. The Merge into a single output option can be used to prevent a separate group of shapefiles being produced for each input .gz file. Caution: Using the Merge into a single output option causes all files and folders under the output folder to be deleted.
  5. Click Convert to start the conversion process.

Applying styles

Styling vector files in QGIS is very flexible. Different methods of styling can be chosen based on the attribute table of the vector file. In this example, we will style the TopographicArea.shp and TopographicLine.shp files produced in the previous step.

The figure below shows the 2 layers in QGIS before styling.

MasterMap with no style

To apply a style to TopographicArea.shp, download and unzip our QGIS rule-based styles for MasterMap Areas. The file contains OSAreasRulesBased.qml. In QGIS, right-click on TopographicArea.shp and select Properties. A new window will open. Click Load Style … and locate OSAreasRulesBased.qml. Click OK.

To apply styles to TopographicLine.shp, download and unzip our QGIS rule-based styles for MasterMap Lines. In QGIS, right-click on TopographicLine.shp, select Properties and click on Load Style … and locate OSLinesRulesBased.qml. Click OK.

MasterMap with style


QGIS can’t connect to any of the plugin repositories

This may happen if your network requires you to use a proxy server to access the internet. If this is the case, you’ll need to configure your proxy server settings. To do this:

  1. Select Options from the Settings menu
  2. Click the Network tab
  3. Enable the Use proxy for web access option and enter your proxy server settings
  4. Click OK