spectre150 and jumpseater, thanks for the information and links. Our history of not that long ago mustn't be allowed to be forgotten!
Particularly for those of us who
just remember the pre-Beeching era.
An interesting website I've found is
Old Ordnance Survey Maps . I'm not sure why there's an equine aspect to it, but basically it allows you to zoom into a map of the UK, then use a fader to see what the map used to show. Or a satellite view overlay. Not 100% coverage, but most of the UK is there. Very interesting as a research tool.
From that website, here's a slightly later version of the OS map showing the line in its entirity:
Interestingly, it is marked as a 'light railway' rather than a tramway - although the branch from Wotton Underwood to Kingswood Lane
is shown as a disused tramway: