1:600 HMS Neptune, on the eve of WW2. HA.DCTs have replaced the quad 0.5" MG in the wings, which have been moved aft, and the 4" AA have been paired and moved farther apart, to allow a whaler to be carried between them. A Fairey Seafox or Swordfish could be shipped on the catapult © Andrew Arthur

At the time of the London Naval Treaty of 1930, Great Britain was already building the first 6"-gun cruisers designed since World War I. Ostensible replacements for the "C" and "D" Class, these were the five 8-gun "Leander" Class ships armed with a new twin 6" gun first tried experimentally in the cruiser Enterprise.
They were handsome ships, with a large single funnel that was a characteristic of the class - and the only ever RN cruiser to have such a funnel. They were completed with four single 4" AA guns, but these were replaced by twins before the outbreak of World War II. During the war a few 40mm and numerous 20mm were added, and late in the war X-turret was removed to reduce topweight.
Achilles was loaned to New Zealand from March 1936 and Leander from April 1937; the former was returned in September 1946 and the latter in May 1944, being replaced by Gambia.
Achilles and Ajax are best remember for their participation in the Battle of the River Plate against the pocket battleship Graf Spee on 13 December 1939. Ajax, Neptune and Orion saw a great deal of action in the Mediterranean, two of them participating in the Battle of Cape Matapan on 27 March 1941 and all three taking part in the Crete campaign in May 1941. Neptune was an integral member of Force "K", the anti-shipping cruiser/destroyer group based at Malta, until she was lost off Tripoli. This incident showed good the great survivability of the British light cruisers, despite light armouring - she plowed through a minefield and only sank after she had struck 4 mines, a tribute to the design.