The main passageway links all the major internal sections of the ship. An important feature of the design of these River Class frigates is this passageway. These ships were designed in 1940 for service in the rough waters of the North Atlantic Ocean protecting merchant ship convoys and fighting submarines. The main passageway allowed the ship’s company to move from one end of the ship to the other without going on the upper deck and at risk of being washed overboard. Older warship designs did require upper deck access to move about some parts of the ship.