Australian troops march up from the beaches to the frontline trenches on the Dardanelles during Gallipolli campaign, WW1

The Gallipoli campaign took place between 25 April 1915 and 9 January 1916. The offensive's ultimate aim was to push through the Dardanelles straits and capture Constantinople, the Turkish capital. If a breakthrough had been achieved, the Turks, who were allied with the central powers (Austria and Germany), would have been unable to prevent Britain and France from joining the Russians in the war against Austria-Hungary and Turkey. After the previous failure of the British and French naval fleets to take the Gallipoli peninsula, the allies felt there was little alternative but to attempt an amphibious landing. On 25 April two landings were made; the main force of 35,000 men under Lieutenant General Hunter Weston landed at Cape Helles. This was supported by a smaller force of 17,000 men from the Australian and New Zealand Army Corps (Anzacs) under General Sir William Birdwood. This force landed at what became known as Anzac cove, a mile north of their intended destination and surrounded by deep cliffs. The Anzacs were to move inland and seize the Sari Bari heights but soon met with a Turkish counter attack. By nightfall the Anzacs had suffered 2,000 casualties and were fighting to stay on the beach. Much of the failure has been attributed to poor coordination and leadership from the British General Sir Ian Hamilton, who chose to command the whole operation from aboard a ship. Another 25,000 men were landed near Anzac Cove and more at Cape Helles in August. The allies made another thrust, but to no avail. Deadlock on the beaches persisted. The whole offensive was finally called off in December and troops evacuated. The Gallipoli campaign cost the lives of more than 100,000 allied and Turkish soldiers with another quarter of a million wounded. Our Picture Shows: Australian troops march up from the beaches to the frontline trenches on the Dardanelles. (Photo by Offiical/Daily Mirror/Mirrorpix via Getty Images)