Do leave a comment if you have any suggestions or would like to contribute to this map. I’d happily give you edit access on Google Maps! The map should appear below, but you can also view a larger version straight in Google Maps.
I’m particularly interested in contributions for Scotland and parts of North-West Europe, but really: any suggestions for anywhere in the world are more than welcome!
(If you have the right permissions, you should be able to edit the map here)