Get yourself a couple of OS maps: OS21 and OS2 and follow the bridleways; Gisburn Forest isn’t far from Skipton if you prefer man made trails. Ilkley Moor has plenty of tracks. Oxenhope, Haworth and Hebden Bridge gives loads of choice. And of course there’s the Yorkshire Dales on the doorstep. I’ll eat my hat if you can’t find any trails from that lot.