The Cyclops class monitor was a group of four ironclad breastwork monitors built for the Royal Navy during the 1870s. They were slightly modified versions of the Cerberus-class monitors. The ships were ordered to satisfy demands for local defence during the war scare of 1870, but the pace of construction slowed down tremendously as the perceived threat of war declined. The Cyclops-class monitors spent most of their careers in reserve and were finally sold off in 1903.