Members of Leeds, Wakefield, Ilkley and Keighley Rock Choir groups sprang up across the moor to give visitors an unexpected musical treat on Saturday..
The choirs eventually gathered together on the Cow and Calf Rocks to put on a a special arrangement of the classic song ‘Hallelujah’.
Other flash-mobs involving Rock Choir groups took place all over the country.
Their efforts were in aid of charity Nordoff Robins.
Rock Choirs span the country and the Ilkley group has been going for the past four years. T
They currently rehearse on Wednesday evenings at St Margaret’s Church Hall every Wednesday evening. Visit www.rockchoir.com for more details.