Intrepid's conversion traded much of her gun battery for capacity to carry roughly one hundred mines, and she later supported the Dover Patrol and forces in northern Russia. Mine loads differed among the sisters, possibly because both deck strength and mine weight varied. Iphigenia's long China Station career and early 1907 conversion show how globally used cruisers moved into mine warfare before the First World War. Intrepid, Iphigenia, and other converted Apollos were ultimately selected as blockships, extending their utility after they had become obsolete as cruisers even though the raids did not always place them exactly where intended.
Notable Point · 58:05-1:02:49
Obsolete cruisers become minelayers and blockships
The class's roomy hulls found new work carrying mines before several ships were filled with concrete for the Zeebrugge and Ostend raids.