Saw this guy walking along a path shortly after a rain shower
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I'm not a snail expert, but I think this might be something else, not Cepaea nemoralis. The shell looks a bit too flat. The lip of the shell has not hardened yet, but when it does C. nemoralis has a dark brown lip.
If you see a snail like this again, turn it over to look for the presence of a hole in the centre of the spiral (an 'umbo'). If the shell has an umbo, its not Cepaea.
There is an ID guide for Cepaea at www.evolutionmegalab.org
University of Edinburgh and Biodiversity Observatory (OU)
Lat/Lng: 50.867571030495, -0.088479638034187
OS grid ref: TQ346093
On a bin outside Bramber House at the University of Sussex