The official directory of the LDWA, the Long Distance walkers Association, for those who are "looking for a clear, and proven, walking route".
What you get is a listing of all official long distance paths, like Offa's Dyke Path or the Pennine Way, but also local ones like the Howdenshire Way or the Gordano Round. With eah walk comes info on the star/end points, which maps (Landranger and 1:25.000) apply, the waymarks (if any) like 'disc with Forest of Avon logo'; and the official website plus a listing of booklets/leaflets and their publishers. That's it - for 638 walks in total! There is also a list of useful addresses (17 pages) and a couple of pages with basic regional maps and all the paths therein, cross-referenced to the walk numbers of the main part of the book.
I like doing long walks, but did not find much useful in here; your mileage may vary!