The Argonauta-class submarine was the first sub-class of the 600 Series of coastal submarines built for the Regia Marina during the 1930s. Some of these boats played a minor role in the Spanish Civil War of 1936–1939 supporting the Spanish Nationalists. Of the seven boats built in this class, only a single one survived the Second World War.
Archimede was the lead ship of her class of four submarines built for the Regia Marina during the early 1930s. She was transferred to the Armada Española of Nationalists in 1937, renamed General Sanjurjo, and served in the Spanish Civil War of 1936–1939.
Evangelista Torricelli was one of four Archimede-class submarines built for the Regia Marina during the 1930s. She served in the Spanish Civil War of 1936–1939, and was transferred to the Armada Española of Nationalists in 1937, renamed as General Mola.
Galileo Ferraris was one of four Archimede-class submarines built for the Regia Marina during the early 1930s. She played a minor role in the Spanish Civil War of 1936–1939 supporting the Spanish Nationalists.
Foca was the lead ship of her class of three submarine minelayers built for the Regia Marina during the late 1930s.
Diamante was one of a dozen Sirena-class submarines, the second sub-class of the 600 Series of coastal submarines built for the Regia Marina during the early 1930s.
Smeraldo was one of a dozen Sirena-class submarines, the second sub-class of the 600 Series of coastal submarines built for the Regia Marina during the early 1930s.
The Settembrini class was a pair of submarines built for the Regia Marina during the late 1920s. They played a minor role in the Spanish Civil War of 1936–1939 supporting the Spanish Nationalists.
The Bandiera-class submarines were built for the Regia Marina during the late 1920s. They played a minor role in the Spanish Civil War of 1936–1939 supporting the Spanish Nationalists.
Luigi Settembrini was the lead ship of her class of two submarines built for the Regia Marina during the early 1930s. She played a minor role in the Spanish Civil War of 1936–1939 supporting the Spanish Nationalists.
Argonauta was the lead ship of her class of seven submarines built for the Regia Marina during the early 1930s.
Fisalia was one of seven Argonauta-class submarines built for the Regia Marina during the early 1930s.
Jantina was one of seven Argonauta-class submarines built for the Regia Marina during the early 1930s. She played a minor role in the Spanish Civil War of 1936–1939 supporting the Spanish Nationalists, and was later sunk during World War II.
Medusa was one of seven Argonauta-class submarines built for the Regia Marina during the early 1930s.
Salpa was one of seven Argonauta-class submarines built for the Regia Marina during the early 1930s.
Serpente was one of seven Argonauta-class submarines built for the Regia Marina during the early 1930s.
Pier Capponi was one of four Mameli-class submarines built for the Regia Marina during the 1920s.
Giovanni Da Procida was one of four Mameli-class submarines built for the Regia Marina during the 1920s. She played a minor role in the Spanish Civil War of 1936–1939 supporting the Spanish Nationalists.
Goffredo Mameli was the lead ship of her class of four submarines built for the Regia Marina during the 1920s.
Tito Speri was one of four Mameli-class submarines built for the Regia Marina during the 1920s.
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