She covered the bombardment of the forts by the superdreadnought on 8 March, and covered minesweepers attempting to sweep in minefields off Kephes on 10 March. During the operation on the 10th, she, the protected cruiser , and several destroyers covered a force of minesweepers. "Canopus" attempted to destroy the searchlights for the Ottoman coastal guns but failed to knock them out. As a result, when the minesweepers tried to clear the mines, they came under intense fire and had to retreat, one of them striking a mine in the chaos. She also took part in the major attack on the Narrows forts on 18 March 1915. During the 18 March attack, a fleet of British and French warships—including "Queen Elizabeth" and the battlecruiser "Inflexible"—would attempt to suppress the forts in daylight, allowing the minesweepers to finally clear the fields unmolested by Ottoman fire. The British ships initially succeeded in inflicting heavy damage on the fortresses, but the battleship and then "Inflexible" began taking serious damage from the coastal batteries. The French battleships also began to take damage, and the battleship struck a mine and exploded.