Except OS data is surprisingly badly suited to this. OS doesn't have a topological (=connected, routable) database of public rights of way. The green lines you

Except OS data is surprisingly badly suited to this. OS doesn't have a topological (=connected, routable) database of public rights of way. The green lines you see drawn on a Landranger map are just that: lines on a map. I don't need to explain how having a routable database would make a project like Slow Ways so much simpler. OS, of course, doesn't have accessibility information like stiles, gates, or surface quality, which OSM often has. I love OS maps, but they are increasingly being marginalised to B2B applications (particularly utilities) and keen walkers. Most UK cyclists have migrated to OSM and, judging from people I see out and about here in the Cotswolds, casual walkers are increasingly going that way too.