 To assess the consequences of infantry having to advance across cratered ground after a mining attack, officers from the Canadian Corps visited La Boisselle and Fricourt where the mines had been blown on the First day of the Somme.Their reports and the experience of the Canadians at The Actions of St Eloi Craters in April 1916, where mines had so altered and damaged the landscape as to render occupation of the mine craters by the infantry all but impossible, led to the decision to remove offensive mining from the central sector allocated to the Canadian Corps at Vimy Ridge.Further British mines in the area were vetoed following the blowing by the Germans on 23 March 1917 of nine craters along no man's land as it was probable that the Germans were aiming to restrict an Allied attack to predictable points.