Boston ? Three hundred immigrants from 79 countries took the U.S. oath of citizenship Friday in an aircraft hangar during the USS John F. Kennedy’s final call in the port of Boston, including seven of its crew members.

The event was the highlight of the second day of the warship’s return to the 35th president’s home state for a five-day farewell visit. It goes out of service later this month.

Later in March, the ship is scheduled to reach its final port of call in Mayport, Fla., for decommissioning. It will be maintained in Philadelphia.

The “Big John,” with a crew of about 4,600, is more than 1,050 feet long, and can carry 70 combat aircraft.

It was christened in May 1967 by the president’s then 9-year-old daughter, Caroline, and entered Navy service in September 1968.

One of two remaining fossil fuel-powered aircraft carriers in the Navy – the rest are nuclear powered – the ship supported Operation Desert Shield in 1990, and was deployed in 2002 to the North Arabian Sea in support of Operation Enduring Freedom.