> 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/areas-and-zones-portfolio/boundary-line/boundary-line-technical-specification/shapefile-tab-and-gkpg/features-shapefile-tab-and-gpkg/historical-and-ceremonial-boundaries-features.md).

# Historical and ceremonial boundaries features

There are several supplementary layers included alongside the main Boundary-Line product. These supplementary layers sit separately to the main `GB` Boundary-Line folder and are included as separate directories in the shapefile and MapInfo TAB file formats.

Features included as supplementary in the supplementary directory are:

* Historical counties
* Ceremonial counties
* Historical European regions (frozen as of 1 April 2021)
* Country

## Feature type attributes <a href="#feature-type-attributes" id="feature-type-attributes"></a>

The following sub-sections provide details about the attributes included with this feature type, their data types in the different output formats, and other important metadata about them.

### fid

Feature identifier added by the software.

* **Attribute Name**: fid (GPKG), Not provided (TAB), Not provided (Shapefile)
* **Multiplicity**: \[1]

### Name

Name of the Ceremonial County, Historic County or Historic European Region.

* **Attribute Name**: Name (GPKG), Name (TAB), NAME (Shapefile)
* **Data Type**: char
* **Size**: 100
* **Multiplicity**: \[1]

### Area description

Classification set to Ceremonial County or Historic County or Historic European Region.

* **Attribute Name**: Area\_Description (GPKG), Area\_Description (TAB), DESCRIPT0 (Shapefile)
* **Data Type**: char
* **Size**: 50
* **Multiplicity**: \[1]

### Link ID

Boundary polygon.

* **Attribute Name**: Not provided (GPKG), Not provided (TAB), LINK\_ID (Shapefile)
* **Data Type**: GM\_Surface


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