The Historic Counties Trust is a Registered Charity which aims to promote public awareness of the history, geography, natural history, architecture and traditions of the historic counties of the UK.The Historic Counties Standard provides a definitive statement of the names, areas and borders of the historic counties of the UK. By providing a definition for the terminology and the names, areas and borders of the historic counties. Maps
http://www.county-borders.co.uk/historiccountiestrust/index.html
Beautiful early maps of England. Also log book of MMS Resolution.
http://cudl.lib.cam.ac.uk/search?keyword=maps&x=0&y=0
The National Library of Scotland has digitised the Ordnance Survey's six-inch to the mile maps for England and Wales. This is the most detailed topographical mapping covering all of England and Wales from the 1840s to the 1950s. Maps are zoomable and the easiest way to find a specific place is by going to the Find by Place tab.
http://maps.nls.uk/os/6inch-england-and-wales/index.html
The National Library of Scotland has digitised over 20,000 maps at high resolution.
http://www.nls.uk/maps/index.html
This site has scanned images of old maps for England, Wales and Scotland arranged by county.
http://freepages.genealogy.rootsweb.ancestry.com/~genmaps
This useful aid is part of the FamilySearch website and enables you to search for places in England on an 1851 map. Boundaries are shown for county, parish, civil registration district, rural deanery, poor law union and hundred. It lists smaller places within each parish, shows the extent of parish registers and much more. By selecting Layers you can also switch to a modern Google map, Streetview or satellite image.
http://maps.familysearch.org/#search
The National Library of Scotland has made freely available historic maps of Scotland, England and Wales which are copyright free and can be used on websites etc.
http://geo.nls.uk/maps/api
Interactive maps of England and some interactive coverage of Great Britain. Includes an overlay for administrative districts.
http://www.magic.gov.uk
View maps of places in England, Scotland and Wales mostly from the 19th and early 20th century.
http://www.old-maps.co.uk
