Town-class cruiser (1936)

Mk XXII turret with rounded contours mounted on Southampton and Gloucester sub-classes

Like their US and Japanese counterparts of that era, the Town-class cruisers were "light cruisers" in the strict terms of the London Treaty, which defined a "light cruiser" as one having a main armament no greater than 6.1 in (155 mm) calibre. All three major naval powers sought to circumvent the limitations on heavy cruiser numbers by building light cruisers that were equal in size and effective power to heavy cruisers. These ships made up for their smaller calibre guns by carrying larger numbers of them.

All of these ships carried BL 6-inch Mk XXIII guns in triple turrets, with the centre gun mounted 30 in (76 cm) behind the two outer guns to prevent interference between the shells in flight and to give the gunners more room to work in.[2] The turret roofs had cutouts at the front to allow extreme elevation, originally intended to give the guns an anti-aircraft capability. In practice the guns could not be trained or manually loaded quickly enough for continuous anti-aircraft fire, so the Royal Navy designed the Auto Barrage Unit (ABU) which allowed the guns to be loaded with time-fuzed shells and then fired when the target aircraft reached a set range. These ships were equipped with the HACS AA fire control system for the secondary armament and the Admiralty Fire Control Table for surface fire control of the main armament.

Mk XXIII turret with squared-off contours mounted on the Edinburgh sub-class

The secondary armament consisted of four twin Mk XIX 4-inch turrets, and two quad pom-poms.[1] Additional light anti-aircraft weapons were added during the war and the 4-inch mounts were converted to Remote Power Control (RPC).[1] Postwar the Birmingham and Newcastle were partially reconstructed in 1949–51 with enclosed bridges, new lattice masts, improved surface fire control and long range radar and an improved but still unreliable version of the Glasshouse Directors with 275 lock and follow radar, with flyplane control [3] for the twin 4 inch guns with elevation speed increased to 15–20 degrees per second, to engage faster jet aircraft. Similar electronic alterations were made to Sheffield but it received less structural alteration. Liverpool was put into reserve in 1952 to preserve it for potential modernisation and Glasgow had a less extensive refit to allow her to be sent quickly if needed in the Suez crisis of 1956. Birmingham, Newcastle and Sheffield had the pom pom and 20 mm armament replaced by 40mm Bofors mounts.[1] Belfast was fitted with MRS 8 HACDT to combine 40 mm and twin 4 inch AA fire and to permit the use of 40 mm proximity fused ammunition as used by the British Army.

All were heavily modified during the Second World War and after the Korean War; Glasgow, Sheffield and Newcastle had one aft turret replaced by two quad 40 mm Bofors guns during the Second World War, since there was insufficient space to fit the needed extra anti-aircraft guns and retain the turret. This was not a problem in the Edinburghs, because they were longer and had more room. They still had substantial modifications to their weaponry, including addition of 40 mm Bofors guns. The addition of radar equipment during the Second World War aided the ships' combat effectiveness.

The first Town-class ship was launched in 1936 and commissioned in 1937, just two years before the outbreak of war. The class saw much service during the Second World War and took part in many famous actions, such as the sinking of the German battleship Scharnhorst. Four, Edinburgh, Gloucester, Manchester, and Southampton, were sunk during the war. The surviving ships continued in active service to the end of the 1950s, some seeing action during the Korean War. The last Town-class ship to be scrapped was Sheffield in 1967. One ship of the Town-class — Belfast — remains, moored on the River Thames in London as a museum-ship of the Imperial War Museum, a role she has performed since 1971.

• HMS Sheffield appeared as an anthropomorphic version of herself in the Japanese browser game Kantai Collection.
• HMS Sheffield, Southampton, Newcastle, Belfast, Edinburgh, Glasgow and Gloucester all appeared as anthropomorphic versions of their respective ships in the Chinese mobile game Azur Lane.
• HMS Belfast and Edinburgh appear in the video game World of Warships.
• HMS Southampton and HMS Belfast appear in the video game War Thunder.
• Ships of the Town Class appeared as HMS Exeter and Ajax in the 1956 film Battle of the River Plate.

• Crown Colony-class cruiser

• Colledge, J. J.; Warlow, Ben (2006) [1969]. Ships of the Royal Navy: The Complete Record of all Fighting Ships of the Royal Navy (Rev. ed.). London: Chatham Publishing. ISBN 978-1-86176-281-8.
• DiGiulian, Tony (2017). "Britain 6"/50 (15.2 cm) BL Mark XXIII". navweaps.com. Retrieved 15 December 2019.
• Brown, David K. (1995). The Design And Construction Of British Warships 1939–1945, Vol 1 Major Surface Vessels. Annapolis, Maryland: Naval Institute Press. ISBN 1-55750-160-2.
• Otter, Ken (2001) [1999]. HMS Gloucester: The Untold Story (2nd ed.). Durham, UK: G.A.M. Books. ISBN 0-9522194-2-5. OCLC 59524624.
• Raven, Alan & Roberts, John (1980). British Cruisers of World War Two. Annapolis, Maryland: Naval Institute Press. ISBN 0-87021-922-7.
• Waters, Conrad (2019). British Town Class Cruisers: Design, Development & Performance; Southampton & Belfast Classes. Barnsley, UK: Seaforth Publishing. ISBN 978-1-5267-1885-3.
• Waters, Conrad (2018). Cruiser Birmingham: Detailed in the original builders' plans. Barnsley, UK: Seaforth Publishing. ISBN 978-1-5267-2497-7.
• Watton, Ross (1985). The Cruiser Belfast. Anatomy of the Ship. London: Conway Maritime Press. ISBN 0-85177-328-1.
• Wingate, John (2004). In Trust for the Nation: HMS Belfast 1939–1972. London: Imperial War Museum. ISBN 1-901623-72-6.

• McCart, Neil (2012). Town Class Cruisers. Liskeard, UK: Maritime Books. ISBN 978-1-904-45952-1.