On 1 September 1921, "Yakumo" was re-designated as a 1st class coast-defense ship and used primarily for training duties in long-distance oceanic navigation and officer training for cadets in the Imperial Japanese Navy Academy. In this capacity, she participated in 13 more voyages in the 1920s and 1930s to Europe, North and South America, and the South Pacific, including a circumnavigation of the globe from August 1921 to April 1922, in company with the armored cruiser . Two of the naval cadets that participated in this cruise were Princes Kuni Asaakira and Kachō Hirotada.