The U.S. Naval Academy will be closed to the general public for several hours tomorrow and Saturday as the Navy welcomes a new leader and says goodbye to another.

On Friday, the Naval Academy hosts a change of command ceremony as Adm. Vern Clark, chief of naval operations, turns over America's fleet to Adm. Mike Mullen. And on Saturday, the academy will hold a funeral for James B. Stockdale, retired vice admiral and Medal of Honor recipient, who died July 5.

Heightened security will surround the change of command ceremony. Clark steps down after five tumultuous years as the Navy's top officer, leading it through an era marked by the Sept. 11, 2001, terrorist attacks and the wars in Iraq and Afghanistan. Visitors will be restricted from entering Naval Academy grounds from 6 a.m. to 1:30 p.m. tomorrow during the ceremony.

Clark, 60, who is retiring, became head of naval operations July 21, 2000, three months before the terrorist attack on the USS Cole in Yemen, which killed 17 sailors. He was the architect of sweeping changes in the service that have included retiring dozens of ships, trimming thousands of jobs and other efforts to make the Navy more relevant and agile in modern warfare. Mullen, 58, a 1968 Naval Academy graduate, is seen as a Clark protege. He worked closely with Clark on many of the Navy reform efforts while serving as his vice chief of operations during 2003 and much of 2004. He is currently commander of Joint Force Command Naples, overseeing NATO missions in the Balkans, Iraq and the Mediterranean. He also is chief of all U.S. naval forces in Europe.

The academy will be closed to general visitors and tours again from 6 to 11 a.m. Saturday during Stockdale's funeral service. The retired vice admiral graduated from the Naval Academy in 1947. His heroism during 71/2 years as a prisoner of war in Vietnam won him a Medal of Honor, the nation's highest award for valor. He was later a vice presidential candidate in 1992, running with Ross Perot.

Stockdale died at his home in Coronado, Calif., at age 81 after suffering from Alzheimer's disease. His funeral service will begin at 8:30 a.m. at the Naval Academy Chapel. Following the service, he will be buried with full military honors in the Naval Academy cemetery.

At the family's request, the Stockdale service is open to friends and family, invited guests, active and retired military members, Naval Academy alumni and those wishing to pay their respects.

Those who plan to attend are asked to park at the Navy-Marine Corps Memorial Stadium one mile away from the academy on Taylor Avenue. Free shuttle buses will run to the Naval Academy between 6:30 and 7:30 a.m. and will return to the stadium after the service.

Visitors are asked to be seated in the chapel by 8 a.m.

Adm. Vern Clark, chief of naval operations, above, will turn over the fleet to Adm. Mike Mullen tomorrow.