"Ocean" and her five sister ships were designed for service in East Asia, where the new rising power Japan was beginning to build a powerful navy, though this role was quickly made redundant by the Anglo-Japanese Alliance of 1902. The ships were designed to be smaller, lighter and faster than their predecessors, the s. "Ocean" was long overall, with a beam of and a draft of . She displaced normally and up to fully loaded. Her crew numbered 682 officers and ratings.