The Royal Canadian Navy (RCN) expanded rapidly and substantially during the Second World War, with vessels transferred or purchased from the Royal Navy and US Navy, and the construction of many vessels in Canada, such as corvettes and frigates. The RCN ended the war with the third-largest naval fleet in the world, and an operational reach extending into the Atlantic, Pacific, Caribbean and Mediterranean.[1][2] The List of Royal Canadian Navy ships of the Second World War lists over 1,140 surface warships, submarines and auxiliary vessels in service during the war. It includes all commissioned, non-commissioned, loaned or hired ships, and all ships crewed by RCN personnel, including 30 depot ships (or "stone frigates"), under the command of the RCN.[3]