dessiato
4 years and I still cry sometimes
But Guildford does have a bit of a hill.There's a brilliant lido in Guildford...
What about Dorking? It's small and has some nice shops to wander past. You wouldn't be there long, and it's easy to get to from Croydon. If you have your own transport, the top of Box Hill isn't too bad for a walk. The footpaths away from the NT centre would be difficult with a pushchair though.

