Snowdon has experienced flurry of edits on OpenStreetMap after the last two long weekends. I happen to be one of the culprits as I've been adding some detail from last July: not least because a family member is planning an attempt on the Welsh 3000ers next month.
The availability of Bing aerial imagery allows a lot more detail to be added, particularly when I can relate it to geotagged photos. I've been able to add:
- walls and fences alongside or crossing tracks;
- bits of marshy ground;
- extend paths which I saw, but didn't walk;
- and, correct alignment of streams and rivers.
Whilst looking at these photos I noticed one of a stile had a roundel indicating the start of Access Land. I've suggested before that it's worth mapping these locations as the complete area covered by access land is only likely to be worked out through gradual accumulation of access points. However, when push comes to shove, I'd not done it myself and couldn't think of an obvious tag for it.
I also found a photo of a large notice for the area, Glyn Rhonwy. This contains a lot of old slate quarries including one huge hole. The notice states that the upper part of the area is access land. However the stile we went over when we came out of the old quarry area had a rather threatening warning notice. This appears from the Ordnance Survey mapping to be exactly where the Access Land starts.
There was another puzzle on the edge of Llanberis. We wanted to avoid walking straight down the road, so had aimed for a footpath marked on the map leaving at a corner of the road above the tea shop at Penceunant Isaf. Checking the OS map today I see that this is also Access Land. All we found was a firmly locked gate.
All in all the Access Land areas in Snowdownia are not that well marked, and are often huge: making them poor targets for mapping. In most cases they're fairly obvious, or are areas where access has been presumed for many years, so adding them to OSM is not a huge help for the walker. Closer to towns and villages there still seems to be plenty of ambiguity. I'm not a fan of the huge intrusive notices that do exist either. They seem inappropriate in a National Park.
Although I added a lot of detail in Snowdoia, I needed to find somewhere else to look at mapping Access Land.
The one place I have been in the past couple of years which is access land and where I probably have enough information to map access land is Parkhouse Hill. This striking little hill, one of a pair of fossil coral reefs (the other, Chrome Hill is shown above), lies just inside Derbyshire in the upper reaches of the valley of the Dove. It is also one of the places which was pretty inaccessible until Access Land was introduced by the 2000 CRoW act.
I took a whole series of photo from the ridge of the hill in September 2009, but without good aerial imagery it was not possible to delineate the outline of the accessible area. Only when writing this post did it occur to me that I could now complete this mapping. Accordingly, I've mapped the access land itself as a relation, and added the tag entrance=access_land where I recorded the relevant sign. The tagging is still pretty tentative, but I hope having something concrete will lead to a common approach.