When the First World War began in August 1914 they were given coastal defence missions, Foresight in the English Channel and Forward on the coast of Yorkshire.

The engines were designed to produce a total of 16,500 indicated horsepower (12,300 kW) which was intended to give a maximum speed of 25 knots.

The ships carried a maximum of 500 long tons (508 t) of coal which gave them a range of 3,400 nautical miles (6,300 km; 3,900 mi) at a speed of 10 knots (19 km/h; 12 mph).

They also carried eight QF 3-pounder Hotchkiss guns and two single mounts for 18-inch torpedo tubes, one on each broadside.

Forward was assigned to coastal defence duties on the East Coast of England; she was present when the Germans bombarded Hartlepool in mid-December 1914, but played no significant role in the battle.

The sisters were sent to the Mediterranean in 1915 and were then assigned to the Aegean Sea a year later and remained there until the end of the war.