the III Division, which helped to defend the Prussian coast from the superior Danish fleet. In April, the III Division was deactivated and the gunboats were transferred to the Reserve Division. After the war, Cyclop took part in a naval review held for King Wilhelm I, followed by a tour of ports in Holstein with now Konteradmiral (Rear Admiral) Jachmann. On 15 September, Cyclop arrived in the new Prussian naval base at Kiel. In late 1864, she became the guard ship at the entrance to the Eider Canal, and she remained in this role through early 1866. During this period, in 1865, the boat's 24-pounder was replaced with a rifled 68-pounder gun. On 14 January 1866, Cyclop was transferred to the coastal fortification at Friedrichsort outside Kiel, along with the gunboat and several cannon-armed shallops; these units formed the II Company of the Naval Artillery Division. Wilhelm I ordered the Navy to begin mobilization on 15 May as war with Austria became likely, leading to the Austro-Prussian War, which broke out in June. Cyclop was transferred to the North Sea along with the ironclad , which led the North Sea Flotilla of gunboats that was commanded by then-Korvettenkapitän (KK—Corvette Captain) Reinhold von Werner. For the duration of the conflict, the flotilla operated out of Geestemünde. Without a naval threat from Austria, the Prussian navy therefore concentrated its effort against the Kingdom of Hanover. On 15 June, Cyclop, Arminius and the gunboat covered the crossing of the Elbe river by General Edwin von Manteuffel and some 13,500 soldiers to attack the city of Hanover. From mid-July to early October, Cyclop served as the tender to the frigate . Cyclop returned to Dänholm on 14 October and was decommissioned there. 1869–1874 Cyclop remained out of service until 22 March 1869, when she was reactivated for service first as a guard ship in Kiel. She conducted a survey off Hörup Haff and Alsen for a shooting range for the old frigate , then assigned to the artillery school. In mid-June, Cyclop and two tugboats towed a floating crane from the AG Vulcan shipyard in Stettin to the Königliche Werft in Kiel. She then took part in the annual fleet maneuvers in August and September, after which her crew was reduced in Kiel for the remainder of the year. In early 1870, Cyclop helped pull the armored frigate free after she ran aground off