# Styling of Land and Sea

This page details an alternative approach for applying a background colour to areas of the map that are not covered by Tidal Water. The solution requires an ESRI shape file defining the spatial extents of each product to be provided as a download on the Ordnance Survey website as found here:

{% embed url="<http://www.os.uk/business-and-government/help-and-support/products/geo-referencing.html>" %}

Most GIS allow a background colour to be applied to the entire display window. In ArcMap this is achieved by right- clicking in the data frame, selecting Data Frame Properties, selecting the Frame tab and setting a background colour. The background colour should be set to be the same colour as TidalWater:

Polygons defining areas of land for the whole world can be downloaded from here: <http://www.naturalearthdata.com/downloads/10m-physical-vectors/> (click on ‘Download land’)

This data is defined in the WGS84 coordinate system. Some GIS will transform this on-the-fly to British National Grid, for others it may be necessary to apply a coordinate transformation first. This data can be added to the map below the two existing layers (ProductExtents and TidalWater). This ensures that only the additional land masses beyond the areas maintained by Ordnance Survey are visible:

<figure><img src="/files/2TXK0df4aw4P3J64Mcwo" alt="Land masses around Great Britain beyond areas maintained by Ordnance Survey shown in purple"><figcaption><p>Land masses around Great Britain beyond areas maintained by Ordnance Survey</p></figcaption></figure>


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