You could try the free browser-based gps Training .
It's very good, you can peruse maps down to 1:25000, as a route planner you can create your own routes, save them etc.

Not sure if this is the right place for this but here goes. Am I the only member who morns the loss of streetmap.co.uk, a simply outstanding web site for walkers, going right back to the early days of the internet when the "net" was a service and not a monetary tool. (I note the LDWA still has links to the web site via it's grid refs - will have to update that I'm afraid). I've searched for an equivalent no luck so far. Have any other members found an equivalent? I'm looking for something accessible through a good old fashioned browser and not some smartphone app and of course should, if possible, be free.