Under bright sunshine, the USS Portland was commissioned in Portland Saturday morning.
The ceremony was held at Terminal Two on the Willamette River.
Speakers at the ceremony included Portland Mayor Ted Wheeler, Governor Kate Brown and Deputy Secretary of Defense Pat Shanahan.
Shanahan says the Portland is "25-thousand tons of diplomacy."
The ship is the Navy's newest San Antonio class landing platform dock. It has a crew of 800 and carries amphibious assault vehicles, air-cushioned landing craft and MV-22 Osprey aircraft.
The ship will be based in San Diego.