1) Almanach city 2) City in Central germany 3) City in East Germany 4) City W of Erfurt 
(from the article `air warfare`) ...never effectively implemented in World War I, was spurred largely by the German air attacks on London. Carried out at first by zeppelin airships, ... ...four-engined airplane. About 80 were built, and they made 400 raids on German targets with the loss of only one plane. The best-known German ... [...city, Thuringia Land (state), central Germany. It lies on the northern edge of the Thuringian Forest, 13 miles (21 km) west of Erfurt.[2 related articles]
German bomber plane, first used in air raids on England in May 1917.