KITTERY — USS Scranton has docked at the Portsmouth Naval Shipyard, where it’ll undergo repairs, maintenance and modernization.

The Los Angeles-class attack submarine arrived Monday with a crew of 16 officers and 122 enlisted sailors.

Nicknamed the “Iron Horse,” the Scranton was commissioned in 1991 and is one of the newer Los Angeles-class subs with structural reinforcements, vertical Tomahawk cruise missile capability, and ship-quieting improvements.

Scranton, whose homeport is Norfolk, Virginia, returned last winter from deployment to the European and Middle Eastern command areas. During the deployment, Scranton covered more than 40,000 nautical miles.