0> In article <20091020141739.184f9fca@crow>, 0> Mark Burton <URL:mailto:markb@ordern.com> ("Mark") wrote: Mark> For the GB data, enabling that test gives over 2000 warnings, the Mark> vast majority of which are real problems that either break the Mark> routing completely or at least give odd routes. I am (slowly) Mark> editing the OSM data to fix the problems. It's incredible what Mark> crap people are happy to put into the OSM database. I get the Mark> impression that most contributors don't give a toss about the map Mark> being routable or not. Whilst that's certainly at least partially true, it's also the case that editing tools can change more than users expect. I've caused at least broken roundabouts myself when joining ways and not noticing that that has reversed their directions.