The U-boat War in World War Two (Kriegsmarine, 1939-1945) and World War One (Kaiserliche Marine, 1914-1918) and the Allied efforts to counter the threat. Over 40.000 pages on the officers, the boats, technology and the Allied efforts to counter the U-boat threat.
Type XXI U-Boat Diesel-Electric Attack Submarine
Munizionamento Cannone Sommergibili Regia Marina - Tecnica - Betasom - XI Gruppo Sommergibili Atlantici
U-boat, German Submarine Warfare in WWI & WWII
U-boat Deck guns - Technical pages - German U-boats of WWII - Kriegsmarine
The 10 Most Legendary Submarines Of WW2 Ranked From Worst To Best
Why were the guns on submarines still usable after being underwater? Wouldn't the guns rust or jam being exposed to sea water? - Quora
The U-Boats of World War Two - Weapons and Warfare
World War I on the homefront Office of National Marine Sanctuaries
This was the secret war off the US coast during World War II
Munizionamento Cannone Sommergibili Regia Marina - Tecnica - Betasom - XI Gruppo Sommergibili Atlantici
