Largest gun mounted on a ship

According to Official Guinness Records,

The largest calibre guns ever mounted on a ship were the nine 45.7 cm (18 inch) guns installed on the Japanese battleships Yamato and Musashi. The shells weighed 1,452 kg (3,200 lb) and could be fired 43.5 km (27 miles).
Yamato and Musashi were the largest battleships ever to sail. Both ships were sunk by American aircraft (in 1944 and 1945) before their massive guns could be fired in anger.

For a complete list of Unknown date records, please visit Unknown date Guinness Records in Japan.

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