The region of the lower Danube has always been of great strategic importance.During the First World War, there were important military Monitor Mounts bases of the Russian Empire, so the Russian command took measures to protect the region.The article analyzes the military-strategic planning in the region on the eve of the war.The history of the activity of the Expedition of Tapes Special Purpose on the Danube is studied.The author, on the basis of archival documents, studied defense works on the lower Danube and the involvement of local people on them.