# Summary

<table data-header-hidden><thead><tr><th width="213"></th><th></th></tr></thead><tbody><tr><td><strong>Theme​</strong> </td><td>Land, Structures, Transport, Water ​[1]</td></tr><tr><td><strong>Collections</strong>​ </td><td>OS Land Features, OS Structure Features, OS Transport Features and OS Water Features Collections </td></tr><tr><td><strong>Feature Types​</strong> </td><td>​Land, Rail, ​Road Track or Path, Structure, Water [1]</td></tr><tr><td><strong>Coverage</strong>​ </td><td>Great Britain​ (‘Excavated or Deposited’, ‘Open Vegetation’, ‘Mineral’, ‘Multiple’, ‘Trees’, ‘Under Construction’ or ‘Water’ [1] topographic area features) [2] [3]</td></tr><tr><td><strong>Geometry</strong>​ </td><td>Polygons​ </td></tr><tr><td><strong>Data Sources​</strong> </td><td>Classification of topographic area features is from existing ground and remote survey methods. Automated classification from OS aerial imagery (25cm) to determine percentage cover value. </td></tr><tr><td><strong>Data Updates​</strong> </td><td>Three-year cyclical revision from OS aerial imagery. Updates are processed up-to-daily into OS NGD. </td></tr><tr><td><strong>Supply Type</strong>​ </td><td>Full supply and Change-Only Update (COU)​. </td></tr><tr><td><strong>Supply Formats​</strong> </td><td><p>GeoPackage or CSV download from OS NGD Select+Build. </p><p>GeoJSON from OS NGD API – Features​. </p></td></tr></tbody></table>

\[1] No percentage value for Water features.&#x20;

\[2] Other features are included in scope where they have a natural land cover, i.e.  areas under construction are included because they are generally sand or bare earth until construction is complete. ‘Constructed’ or ‘Made’ features are out of scope.&#x20;

\[3] Only features above the Mean High Water (Springs) line have a percentage value.&#x20;


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