In February 1915, "Lord Nelson" was ordered to the Dardanelles to participate in the Dardanelles Campaign. She departed Portland on 18 February and joined the British Dardanelles Squadron at Mudros eight days later. She took part in the bombardment of the inner forts and supported the initial landings in early March. The Ottoman Turkish forts engaged her heavily on 7 March and hit her several times, including by a stone cannonball which landed on the deck and was kept as a souvenir by the Flag Officer, Arthur Baker, at Longcross Church; she suffered damage to her superstructure and rigging and was holed by one hit below the waterline which flooded two coal bunkers. After repairs at Malta, the ship returned to take part in the main attack on the Narrows forts on 18 March. Later she bombarded Ottoman field batteries on 6 May prior to the Second Battle of Krithia.