关东州
The was the major navy base for the Imperial Japanese Navy in the Kwantung Leased Territory before and during Second Sino-Japanese War. Located in at Ryojun ), (present-day Lüshunkou, China, The Ryojun Guard District was responsible for control of the strategic seaward approaches to Manchukuo and to north China and for patrols in the Yellow Sea and along the China coastlines. It was disbanded in 1943.