🌐EnglishEnglishFrançaisPolskiالعربيةفارسی中文EntityQ7391735· pop 6· linked from 137 articlesSM UC-621916 Type UC II submarineConnectionsnaval mineEntitygross register tonnageEntityCategories1916 shipsGerman Type UC II submarinesMaritime incidents in 1917Ship infoboxes without an imageShips built in Bremen (state)U-boats commissioned in 1917U-boats lost with all handsU-boats sunk by minesU-boats sunk in 1917World War I minelayers of GermanyWorld War I shipwrecks in the North SeaWorld War I submarines of Germany