Allied transport ships burn in Suda Bay following a German bombing raid. As in Greece, command of the air was decisive in gaining victory against the Allies in Crete.The strategic importance of Crete for the Balkans and the Mediterranean has been recognised throughout recorded history. It is the largest island in the Aegean and occupies a central position in the eastern Mediterranean. Developments in naval and air warfare by 1939 had· enhanced its importance, and the harbour at Suda Bay, as the largest in the Mediterranean, was an obvious base for naval operations.
Under British control its airfields, properly exploited, could threaten the Balkans as far as the oilfields in Rumania; if available to an enemy, they could endanger British sea communications through the Mediterranean to Alexandria, and the island itself could be used as a staging post for reinforcements to any part of the Western Desert.
The island is about 160 miles long from west to east and about 36 miles wide from north to south. It is dominated by four mountain ranges. The south coast has four harbours, but these are fit only for fishing-boats; the best harbours- Suda Bay, Retimo, and Heraklion-are on the north coast. The airfields, so valuable to whoever controls them, are all in the neighbourhood of these latter ports. Communications in 1941 were primitive. The important roads were few, bad, and mainly concentrated on the north coast, while there was only one lateral east-west road. Strung along this road were the ports and the airfields, easily accessible to air attack from the mainland of Greece. The road could take only one line of traffic, and its bridges were unsafe for vehicles over 7 tons; there was no mesh of subsidiary roads to relieve pressure on it, for the roads running south were little but cart-tracks, and only three of these ran right across the island. There were only three local narrow-gauge railways in the island and these were of no military importance, while telephone and telegraph facilities were negligible.
From the point of view of a potential defender of the island, the only advantages afforded by topography were the ruggedness of the country inland from the north coast, which made outflanking manceuvres slow and laborious; and the fertile tracts on the north coast, which had many groves of olives and almond trees to give good cover to troops. These potentialities were realised by the British from the outbreak of war- but, because of Greek neutrality, nothing could be done until Italy invaded Greece at the end of October 1940. Plans had then been put in train for the island's occupation in brigade strength, with projected reinforcement by the Marine Naval Base Defence Organisation (MNBDO) and a large complement of heavy and light anti-aircraft guns.