The 11th (Service) Battalion (Accrington) East Lancashire Regiment.
Part of the Kitchener Army consisted of the "Pals" Battalions, consisting of units raised from a given location, sometimes from a single employer (I think there was a Glasgow Tramways Bn for example).
Tragically, the first time most of the Pals Battalions saw action was at the Battle of the Somme, 1st July 1916.
The Accrington Pals advanced towards the village of Serre, with the Sheffield City Bn on their left, and the 1st & 2nd Barnsley Pals Rear and Left.
By the end of the battle, 234 men of the Accrington Pals were killed, 131 with no known grave and 350 were wounded, out of a total strength of 720.
A very good book is available, Accrington Pals, by William Turner, ISBN 0-85052-36-5.