Dive Diary: Rio de Janeiro Maru
The Rio de Janeiro Maru was built in 1930 as an eight deck ocean liner by O.S.K. Line (Osaka Shosen Kabushiki Kaisha) and between the World Wars she served as a ocean liner, doing four month turns around the globe. She was requisitioned for war in 1940 and served first as a submarine depot ship, and was later reassigned as a…