This black-and-white photograph, which was taken between 1915 and 1917, shows the crew of a German submarine of the UC 1 type. The men are standing on the surfaced submarine. This type of submarine was introduced in 1915 and was mainly used for laying mines.
The German Navy in the First World War, black-and-white photograph, ca. 1915–1917, photographer: German official photographer; source: Imperial War Museum (Q 20220), http://www.iwm.org.uk/collections/item/object/205193147, © IWM.