'nidirect brings together lots of information from government departments and agencies, written in language that is easy to understand. And, you don't need to know the workings of government to find what you are after.'

Access to detailed map showing the 'Administrative Units of the United Kingdom'

The Map was produced by Maximilian Dörrbecker

List of Counties of the United Kingdom [Wikipedia] | Administrative Regions of the British Isles [Genuki]

'Vast geographical encyclopaedia, featuring details of towns, villages, bens and glens from the Scottish Borders to the Northern Isles. The first comprehensive gazetteer produced for Scotland since 1885, it includes tourist attractions, industries and historical sites, together with histories of family names and clans, biographies of famous Scots and descriptions of historical events associated with Scotland.'

Bruce Gittings [University of Edinburgh] | Royal Scottish Geographical Society

'The Gazetteer provides an exhaustive Place Name Index to Great Britain, containing over 50,000 entries. It lists the historic county and the main administrative areas in which each place lies.'

Does not cover Northern Ireland.

Association of British Counties

'Much of the 20th century was spent searching for an idealised system of local government. The most sweeping change in that period was the Local Government Act 1972, which resulted in a uniform two-tier system of counties and districts being introduced in 1974; however, further waves of reform has led to a more heterogeneous system in use today ...'

Wikipedia

'From 1 April 2015, 11 new councils took over from the previous 26 under a programme of reform. Find out more about how these changes affect you, including information on your new council, its services and rates.'

nidirect

Reform of local government in Northern Ireland [Wikipedia]

'Location details, opportunities and restrictions for accessing military owned land in the United Kingdom.'