Tsukuba-class cruiser

Tsukuba at anchor at Kure, after 1913
Class overview
NameTsukuba
BuildersKure Naval Arsenal
Operators Imperial Japanese Navy
Preceded byKasuga class
Succeeded byIbuki class
Built1905–1908
In service1907–1922
Planned2
Completed2
Lost1
Scrapped1
General characteristics
TypeArmored cruiser (later reclassified as battlecruiser)
Displacement13,750 long tons (13,971 t)
Length450 ft (137.2 m)
Beam75 ft (22.9 m)
Draft26 ft (7.9 m)
Installed power20 Miyabara water-tube boilers, 20,500 ihp (15,300 kW)
Propulsion
Speed20.5 knots (38.0 km/h; 23.6 mph)
Complement820
Armament
Armor

The Tsukuba-class cruisers (筑波型 巡洋戦艦, Tsukuba-gata jun'yōsenkan) were a pair of large armored cruisers (Sōkō jun'yōkan) built for the Imperial Japanese Navy (IJN) in the first decade of the 20th century. Construction began during the Russo-Japanese War of 1904–05 and their design was influenced by the IJN's experiences during the war. The British development of the battlecruiser the year after Tsukuba was completed made her and her sister ship Ikoma obsolete, as they were slower and more weakly armed than the British, and later German, ships. Despite this, they were reclassified in 1912 as battlecruisers by the IJN.

Both ships played a small role in World War I as they unsuccessfully hunted for the German East Asia Squadron in late 1914. They became training ships later in the war. Tsukuba was destroyed in an accidental magazine explosion in 1917 and subsequently scrapped. Her sister was disarmed in 1922 in accordance with the terms of the Washington Naval Treaty and broken up for scrap in 1924.