The markers on the map can be filtered three different ways (in combination if desired):

1. By Date: specify a Start date and/or an End date and click the "Apply Dates" button. To reset, blank the date fields and click the button again. Either date may be specified by itself or in combination. When a Start date is specified, only offices that were in existence after that date are displayed. When an End date is specified only offices that were in existence before that date are displayed. If "Exact Dates" is checked then only offices which match the specified dates exactly will be shown.

2. By Type: check or uncheck the "Select Types" check boxes to display or not display offices of that type. If an office is of the selected type within whatever date range is specified then it will be displayed.

3. By Post Town or RSO: Expand the lists in the right-hand side bar to see the Post Towns, Railway Sub-Offices and Post Towns external to the County. RSOs that were also Post Towns are listed under Post Towns. Check the check box next to a Post Town/RSO to just see the offices under it - filtered by date range and/or type if specified. Check multiple Post Towns/RSOs to see offices under any of the offices checked. Uncheck the Post Town/RSO(s) to revert back to the whole county display.

The display will automatically zoom to show whatever offices need to be displayed - check the "Static Zoom" check box to freeze the zoom level. Uncheck it to allow automatic zoom.

Click on any of the markers, or on the underlined links in the right-hand side-bar, to display details on an office.

Please email any corrections or suggestions.

The County boundaries (with the exception of the City of Bristol) are from "The Historic County Borders Project".

"The primary source data for the borders of the historic counties of Great Britain shall be that obtained by the Ordnance Survey during its first national survey of Great Britain and presented on the resultant First Edition 1:2500 and 1:10560 maps"  [c. 1891].

The boundary for the City of Bristol is taken from an Ordnance Survey map of 1832, surrounded by the current administrative area.

The Post Office data for the map is taken from Ken Smith's list of offices - see here.