This is the version of the Ordnance Survey publish by Cassini. It has a good search interface and ability to browse, but be prepared for some frustration. As I found for the town of Carmarthen, the search takes you to a map with the town in the corner and no ability to scroll to an adjacent map.
I wasn't very impressed with Ancestry's UK maps either. I looked up Hornchurch which I knew was in Essex in 1926 and found it indexed under Havering--the London Borough it has only been in since 1965.
ReplyDeleteFor close up maps of the UK online I recommend http://www.visionofbritain.org.uk/maps/
A Vision of Britain provides Ordnance Survey maps of different periods so you can see how parish and district boundaries moved over time. The county maps are now downloadable--huge files but can be broken down into smaller sections.