After operational training in southern Californian waters, "Portland" steamed for the Aleutians late in May, arriving on 11 June and bombarding Kiska on 26 July. After covering a reconnaissance landing on Little Kiska on 17 August, she called at Pearl Harbor on 23 September, there to San Francisco in early October, then back to Pearl Harbor in mid-October. From November 1943 to February 1944, "Portland" participated in the Gilbert and Marshall Islands campaigns. She bombarded Tarawa on 20 November supporting landings there for several days. She was lightly damaged by a friendly depth charge when a nearby destroyer erroneously detected a Japanese submarine. In December 1943 she moved to the Marshall Islands escorting the new "Essex"-class carrier . While "Lexington" came under air attack, none of the Japanese planes came within range of "Portland" and she did not open fire. She returned to Pearl Harbor on 25 December, and went into drydock to repair her rudder and propellers.