The Electronic Map covers the whole of England and Wales, and is organised by Ordnance Survey Sheet number. The map consists of scanned bitmap images of the Ordnance Survey one inch to the mile (1:63,360) New Popular Edition maps (1945-8) with National Grid. It contains the boundaries of some 18,233 places, and is arranged as three electronic 'layers'. The first is a scan of the Ordnance Survey maps stored as grey tone sheet images. This enables Ordnance Survey physical, cultural and place-name content to be readily visible in the background for orientation and general location purposes, while not obscuring the added boundary and reference number material. The second layer consists of the boundaries, stored as solid red lines; and the third layer contains the reference numbers that link places on the map to the gazetteer/metadata dataset that accompanies the maps.The maps are available on CD-ROM in Adobe Illustrator? v.6 (?45 plus P&P) or Adobe Acrobat PDF? (?15 plus P&P). Adobe Illustrator format is recommended if you already have the software (as it enables you to edit the maps and select the layers to view). However, the Adobe Acrobat PDF format is perfectly suitable for viewing the maps, and the the necessary reader software will be supplied.