# Summary

A Field Boundary is a line feature representing the field boundary features adjacent to, or contained within, areas of agricultural land, trees, rough grassland, or heath. It also includes features adjacent to land in the Rural Payment Agency's (RPA’s) Rural Land Register (RLR) that are situated within urban areas in England. Field Boundary features replicate all, or part of, the underlying OS NGD Structure (Built Obstruction) Line and are classified as Tree Canopy, Wooded Strip, Hedge, Wall, Other, or Unknown (in hierarchy order).

<table data-header-hidden><thead><tr><th width="203"></th><th></th></tr></thead><tbody><tr><td><strong>Theme</strong>​</td><td>OS NGD Structures</td></tr><tr><td><strong>Collection</strong>​</td><td>OS Structure Features</td></tr><tr><td><strong>Feature Type</strong></td><td>​Field Boundary</td></tr><tr><td><strong>Coverage</strong>​</td><td>Great Britain​, in Rural and Moorland areas. Features adjacent to, or contained within, areas of Agricultural Land, Trees, Rough Grassland and Heath, OR features adjacent to land in the Rural Payment Agency’s (RPA) Rural Land Register (RLR) that are situated within urban areas in England.</td></tr><tr><td><strong>Geometry</strong>​</td><td>Line​s that represent physical barriers (Built Obstruction).</td></tr><tr><td><strong>Data Sources</strong>​</td><td>Automated classification using OS aerial imagery, digital surface models (DSM), digital terrain models (DTM), and ‘Built Obstruction’ Structure Lines from OS NGD. </td></tr><tr><td><strong>Data Updates​</strong></td><td>3-year cyclical revision from OS aerial imagery (25cm). When the topographic area updates in 10km-by-10km areas are complete, the automated process is run to classify and calculate height and width values. When available, 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 Format</strong></td><td><p>GeoPackage and CSV (OS NGD Select+Build);</p><p>GeoJSON (OS NGD API – Features)​; vector tiles (OS NGD API – Tiles)</p></td></tr><tr><td><strong>Licensing Terms</strong></td><td>Available to customers under PSGA licensing terms. <br>Commercial terms are available for OS Partners based on the number of hectares.</td></tr></tbody></table>


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