> 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/products/maps-and-imagery-portfolio/os-open-zoomstack/os-open-zoomstack-technical-specification/sea-extent-and-name-languages.md).

# Sea Extent and Name Languages

## Vector Tile Sea Extent <a href="#bookmark5" id="bookmark5"></a>

If you’re creating an interactive web map, you may wish to restrict the ability to pan beyond the extent of the sea polygon. The necessary coordinates for this are:

* -11.3, 49.4 - Southwest coordinates
* 3.5, 61.5 - Northeast coordinates

## Name Languages <a href="#bookmark6" id="bookmark6"></a>

The names layer is multi-lingual. For settlement names (Cities, Towns, Villages, etc.) the *name1* attribute will contain the accepted or English name and *name2* will contain the Welsh, Gaelic or English name.

The *name1language* and *name2language* attributes let you select which names to display. For example, if you want to show all the Welsh language names then you can use these attributes to filter them out and render them on your map.

These are the attribute values in the language fields:

* cym = The name is in the Welsh language.
* eng = The name is in the English language.
* gla = The name is in the Scottish Gaelic language.
* NULL = The language type is not set if there is only one name, or if there are two names, and the language of one or both of the names is not recorded as English, Welsh or Gaelic.


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