The arrival of hostile submarines caused the dispersal of the fleet and transports, leaving the main supply of the army to indefatigable trawlers, fleet-sweepers, and other small craft, and involving the removal of General Headquarters from sea to land. For some days the _Arcadian_ had a merchant ship lashed each side of her for protection, but the navy refused further responsibility, and at the end of May Sir Ian and his Staff put ashore on Imbros. There was no choice, for Tenedos was largely occupied by the French; Mudros was too distant; and on the Peninsula no place could be found for General Headquarters without entanglement in the headquarters of divisions or the Anzac Corps. Kephalos Bay was nearly equidistant from both landings (about twelve miles from Anzac, and ten from Helles), with both of which it was rapidly connected by telephone and telegraph. Accordingly, the camp was pitched among the sand dunes at the base of the Kephalos promontory, looking over the bay to jagged mountains beyond. A small stone pier was built, for Headquarter use only, whence Sir Ian visited the Peninsula on a torpedo boat three or four times every week. On the opposite side of the bay the navy constructed a similar but longer pier, and sank a collier and two smaller Italian vessels to form a breakwater against the north. Thus a fairly sheltered port was made for the trawlers running daily to the Peninsula with drafts and supplies, and for those which returned to Mudros for more. Level ground, stretching over a mile south-west, was used as a store-depôt, a rest-camp, and a training-place for reinforcements. Up in the hills a camp was laid out for Turkish prisoners, who worked at road-making. Two or three miles away, above a salt marsh, and upon the south coast, were stations for R.N.A.S. aeroplanes, which numbered about 60 in all, but never counted more than 25 or 30 in action. In the later months of the expedition, General Headquarters were removed to the entrance of the deep valley leading up to the pass, because gales, dust storms, hostile aeroplanes, and want of water and shade upon the sand dunes added, as might have been foreseen, to the inevitable discomforts of war.