After Turkey joined to fight along Germany in 1914 Russia demanded its allies to open up a new front directly against Turkey. Britains war-minister lord Kitchener made a plan of invading the peninsula of Gallipoli. The operation was a disaster.
The invasion of Gallipoli started in february 1915 with an naval attack. After first few successes the operation suffered a setback, when three battleships ran into mines. The first amphibious assault was delayed and Turkish troops had more time to prepare their lines.
25th of April the second assault started and the Allies managed to get some foot at the peninsula only to discover that they were sitting ducks to Turkish artillery. Also when days turned to weeks the Allied faced some severe diseases and lost a lot of men becouse them also. In the first days of August the death toll went past 30.000, but the Allied just sent more men to solve the situation. Finally in January 1916 Allies retreated. There is a huge variety in estimated death tolls, but the most common would be about 50.000men dead and 150.000wounded. The Allied forces didnt archieve anything in the operation except the damage done to Axis´ manpower.