The Nicholson Waterways Guides are absolutely invaluable to boaters
Their guide for the Grand Union Canal is always open on the dashboard while I’m driving.
They show the route of the canal, which side the towpath is on, the location of locks and winding holes and boatyards and marinas.
They also list canalside pubs, drinking being something of a hobby for many boaters, especially if the pubs have their own moorings and real ale. Car drivers would, you hope, refrain from going to the pub during a journey but it’s part and parcel of boating.
The writers of the guides are also a bit church-obsessed and never fail to mention if there’s a nice set of 15th century brasses nearby.
So, Nicholson Waterways Guides are really useful to canal and river boaters. However, if you try to arrange to meet someone they are next to useless. Try telling a car owner with an AA road map that you’ll meet them by bridge number 129, you know, it’s next to lock 38.