Those of the Aberdare group were originally named after coastal towns, watering places and fishing ports, some of which happened to be hunts by coincidence.

However, all were soon renamed after inland locations to prevent confusion caused by the misunderstanding of signals and orders.

Their counter-mine equipment consisted of Oropesa floats to cut the cables of moored mines.

Six ships were completed as survey vessels, and the majority of the Aberdare group arrived too late to see service during the First World War.

At least two ships from the Flotilla (Ross and Lydd) were detailed to collect troops from the harbour mole.

Five ships were lost during the war, and a further vessel, Widnes was beached in Suda Bay, Crete in May 1941 after being bombed by German aircraft.