the black sea map, from July 24th 1915 to may 7th 1918, is ready.
legend:
red line: front line in 1914; Trazbon was captured by russian forces on april 1916, but recaptured by ottoman forces on february 11th 1918.
mayor russian harbours: Sevastople, Yalta and Novorossik.
iron crosses: Costantinople Flottolla's u-boats attack zones.
red squares: bulgarian submarine attack zones.
Romania is entered in war on august 17th 1916 and invaded by Central Powers' forces on may 1918.
the romanian navy was formed only with costal gun-boats and armed drifters.
the bulgarian submarine "Podvodnik No 18" (ex UB-8)entered in service with the bulgarian navy on may 25th 1916; it sank only two ships in its carrier.
it was armed wth an austro-hungarian 37mm rapid fire deck gun.
bulgarian flag:
skinn of the submarine:
