German submarine U-4 (1935)

German submarine U-4 was a Type IIA U-boat of Nazi Germany's Kriegsmarine before and during World War II. She was one of the longest lasting German submarines of the period, primarily since half of her time was spent on training duties in the Baltic Sea.

German submarine U-4 (1935)

German submarine U-4 was a Type IIA U-boat of Nazi Germany's Kriegsmarine before and during World War II. She was one of the longest lasting German submarines of the period, primarily since half of her time was spent on training duties in the Baltic Sea.