The map provided here is based on the postcode of the venue.
Royal mail are very good at allocating postcodes to buildings
but much less good at lakes and rivers. Therefore where a
venue does not really have a postcode I have tried to find a
postcode that is as close as possible to the venue. This might
be that of a nearby hotel or even the village post office. You
should therefore always ensure you have proper directions
for the last half-mile or so to the venue.