The British prepared for their risky deployment upstream. Troops had already been aboard landing ships and drifting up and down the river for several days when on 12 September Wolfe made a final decision on the British landing site, selecting L'Anse-au-Foulon. Wolfe's plan of attack depended on secrecy and surprise — a key element of a successful amphibious operation — a small party of men would land by night on the north shore, climb the tall cliff, seize a small road, and overpower the garrison that protected it, allowing the bulk of his army (5,000 men) to ascend the cliff by the small road and then deploy for battle on the plateau. The operation proved a success, leading to the surrender of the city, and heavily influenced subsequent engagements.