For the remainder of the conflict, Arminius operated out of Geestemünde, under the command of Reinhold Werner, and the mere appearance of Arminius caused several Hanoverian coastal batteries to surrender.[10] On 15 June, Arminius and a pair of gunboats, Tiger and Cyclop, covered the crossing of the Elbe river by General Edwin von Manteuffel and some 13,500 soldiers to attack the city of Hanover.[10][11] By the end of the month, the Prussian army had decisively defeated the Austrians at Königgrätz and ended the war.[10] On 3 October 1866, the ship raced the US Navy's monitor USS Miantonomoh in Kiel; Arminius was two knots faster than the American vessel.[6] In 1870, the ship had her sailing rig removed.[12]