Why did the triple entente wage a campaign on the gallipoli peninsula?

The Gallipoli Campaign of 1915-16, also known as the Battle of Gallipoli or the Dardanelles Campaign, was an unsuccessful attempt by the Allied Powers to control the sea route from Europe to Russia during World War I. The campaign began with a failed naval attack by British and French ships on the Dardanelles Straits in February-March 1915 and continued with a major land invasion of the Gallipoli Peninsula on April 25, involving British and French troops as well as divisions of the Australian and New Zealand Army Corps (ANZAC). Lack of sufficient intelligence and knowledge of the terrain, along with a fierce Turkish resistance, hampered the success of the invasion. By mid-October, Allied forces had suffered heavy casualties and had made little headway from their initial landing sites. Evacuation began in December 1915, and was completed early the following January