of the vessels were used as piers (e.g., in Rafina, ) and breakwaters (e.g., in Agios Georgios, Methana, ). Due to the need to deliver necessary raw materials (such as oil, weapons, ammunition, food and drugs) through mined river currents, Adolf Hitler ordered the production of 50 concrete ships for different purposes. Most were concrete barges made for oil transportation from Romania, and needed raw materials that were driven to the Baltic front. A smaller number of ships was intended for transporting food (specializing in cold storages). The most valuable ships were the specialized ship-hospitals, which evacuated seriously wounded and "important" soldiers to German hospitals along rivers. Japan Several concrete ships were aground on the west beach of Iwo To (Iwo Jima) in Japan, , to make a breakwater by the US forces in 1945. Most of them were broken by typhoons but one was used as a pier. Japan built four concrete ships named Takechi Maru No. 1 to 4 () during World War II. After the war, two of them turned into a breakwater in Kure, Hiroshima, . See also Concrete canoe Capella (concrete ship) Concrete Ship, former concrete hospital ship Trefoil class concrete barge References External links History of ferro-concrete ships Comprehensive list of ferro-concrete builders Images of concrete vessels from the National Monuments Record Photographic record of the construction and launch of the Cretemanor at Preston and the Seacraft Concrete Co on the Mersey. "Pour in the Concrete and Take Out a Ship", February 1919 Popular Science "How Pour Ships Are Made" , June 1943, Popular Science Ship types Concrete Barges