I did a ride on the SDW and at about mile 70 as we were going west to East- We met a large organised walking group going East to west. The walkers were spread out over about a mile and we met them on a downhill. The walkers were 4 or 5 abreast across the trail and you had a steady array of Knackered riders meeting them head on. I had the horn working overtime and we could not make all the walkers notice us. In the end we took to the fiels alongside but had to rejoin the track just as the trail narrowed and went uphill. Still bibbing the horn and a group of walkers were having a chat in the gateway. Bibbed the horn- no response- Yelled out "Clear the Path" no response- in the end I did the Tandem trick of me getting off the bike and opening the gate---Into them. Bit of response then and one said "You ought to get a bell"--Her second response was-"No need to use language like that"