Ro-40 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in September 1943, she served in World War II...

Ro-33 was an Imperial Japanese Navy Ro-33-class submarine. Completed and commissioned in November 1935, she served during World War II in the South China...

Ro-41 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in November 1943, she served in World War II...

Ro-34 was a Kaichū type submarine of the K6 sub-class built for the Imperial Japanese Navy. Completed and commissioned in May 1937, she served in World...

Ro-61, originally named Submarine No. 72, was an Imperial Japanese Navy Type L submarine of the L4 subclass. She was in commission at various times from...

Ro-65 was an Imperial Japanese Navy Type L submarine of the L4 subclass. First commissioned in 1926, she served in the waters of Japan prior to World War...

most varied and powerful submarine fleets. The Imperial Japanese Navy (IJN) acquired its first submarines during the Russo-Japanese War on 12 December 1904...

Ro-110 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in July 1943, she served in World War II, operating in the Indian...

Ro-50 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in July 1944, she served in World War II, conducting...

Ro-44 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in September 1943, she served in the central...

Ro-45 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in January 1944, she served in the central Pacific...

Ro-42 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in August 1943, she served in World War II and...

Ro-1, originally named Submarine No. 18, was an Imperial Japanese Navy Type F submarine of the F1 subclass. She and her sister ship Ro-2 were the first...

Ro-35 was an Imperial Japanese Navy Kaichū type submarine, the lead unit of the K6 sub-class. Completed and commissioned in March 1943, she served in...

Ro-38 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in July 1943, she served in World War II and...

The Kaichū type submarine (海中型潜水艦, Kaichū-gata sensuikan) submarines were double-hulled medium-sized submarines of the Imperial Japanese Navy during World...

Ro-64, originally named Submarine No. 79, was an Imperial Japanese Navy Type L submarine of the L4 subclass. First commissioned in 1925, she served in...

Ro-2, originally named Submarine No. 21, was an Imperial Japanese Navy Type F submarine of the F1 subclass. She and her sister ship Ro-1 were the first...

Ro-43 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in December 1943, she served in World War II...

Ro-4, originally named Submarine No. 32, was an Imperial Japanese Navy Type F submarine of the F2 subclass. The Type F submarines were the first truly...

Ro-112 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in September 1943, she served in World War II, operating off Australia...

Ro-100 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in September 1942, she served in World War II, operating in the...

Ro-37 was an Imperial Japanese Navy Kaichū type submarine of the K6 sub-class. Completed and commissioned in June 1943, she served in World War II and...

Ro-106 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in December 1942, she served in World War II, operating in the...

Ro-102 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in November 1942, she served in World War II, operating in the...

Ro-66 was an Imperial Japanese Navy Type L submarine of the L4 subclass. First commissioned in 1927, she served in the waters of Japan prior to World War...

Ro-108 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in April 1943, she served in World War II, operating in the Solomon...

Ro-5, originally named Submarine No. 33, was an Imperial Japanese Navy Type F submarine of the F2 subclass. The Type F submarines were the first truly...

Ro-60, originally named Submarine No. 59, was an Imperial Japanese Navy Type L submarine of the L4 subclass. She was in commission from 1923 to 1934 and...

Ro-115 was an Imperial Japanese Navy Ro-100-class submarine. Completed and commissioned in November 1943, she served in World War II, operating in the...