Counties of Britain consists of groups of cards representing various counties of Britain. A group is comprised of a key card, listing all the towns (or districts) of a county, as well as a card for each of the listed towns, each having an illustration of the town and interesting, town-specific facts about industry, attractions or population.
Players compete to complete groups of cards, thus having a full county. The player who completes the most counties wins the game. In this sense, the game plays like 'go fish'.
The game was sponsored by the London and North Eastern Railway of the time and has reproductions of famous railway posters on the back of each card.
Counties of Britain is similar to Counties of England, also published by John Jaques of London.