Submarines of the Imperial Japanese Navy
Imperial Japanese Navy submarines originated with the purchase of five Holland type submarines from the United States in 1904. Japanese submarine forces progressively built up strength and expertise, becoming by the beginning of World War II one of the world's most varied and powerful submarine fleets.
Japanese submarine I-201
The "I-201"-class submarines were derived from the experimental high-speed Submarine "No.71". They displaced surfaced and submerged. The submarines were long, had a beam of and a draft of . The boats were the deepest-diving Japanese submarines of the war and had a diving depth of .