During the Allied preparations for the Battle of Vimy Ridge (9 – 12 April 1917) the mines fired on the first day of the Somme became the object of strategic considerations. In order 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. Their reports and the experience of the Canadians at St Eloi 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.