 "Nautilus" took part in the annual fleet maneuvers in August and September 1907 and 1908 before being decommissioned in Kiel; her role in the peacetime fleet was then taken over by her recently commissioned sister ship .In 1909–10, "Nautilus" was modernized at the "Kaiserliche Werft" (Imperial Shipyard) in Kiel.Her stern overhang was extended by , bringing the ship's overall length to , and her superstructure deck was extended further aft.