OpenStreetMap
I've been mapping the odd road and a few footpaths in Aberdovey (Aberdyfi), based on some traces while on holiday there a couple of weeks ago. Not a lot, and I didn't note down most of the names, so it is just what I can remember, but perhaps I'll add some more next time I'm there.
Quite a few of my traces go beyond the coastline, including the end of a residential street and a public garden, which I am pretty sure are above the high tide mark. However, I am bit dubious about starting to shift the coastline, as I could only shunt it a few metres to go around the edge of what I have traced; I wouldn't be able to confidently state that I am moving it to the real average high tide mark, so I'll probably leave said street and garden out for now.
Also, still trying to decide whether the windy road (showing in grey in Mapnik) is "residential" or "unclassified" - anyone with local knowledge want to chip in?
Discussion
Comment from dankarran on 25 August 2009 at 22:55
That's a beautiful little place, I was there some years ago.
Regarding the data you want to add that overlaps the coast, I would suggest to add it in and move the coast around it, trying to keep the shape as best as possible. Coastlines aren't very accurate in many places, so if you're getting pretty consistent GPS results, you should probably trust that over the coastline that was imported.
Comment from davespod on 27 August 2009 at 07:21
Thanks. I might give it a go.