The Court of Valor veterans' memorial at Prospect Hill Cemetery will be updated Saturday as part of a commemoration of the 11th anniversary of the Sept. 11, 2001, terrorist attacks.

The public is invited to the service, one of the cemetery's most well-attended events, to observe a tribute to local firefighters and police officers and those who died during the terrorist attacks. Tent seating is provided for more than 600, but cemetery president Jack Sommer said people should arrive early.

Local fire and police departments have helped to plan the event, which includes a ladder truck salute and a line-up of local emergency vehicles to flank the cemetery entrance.

Program highlights include an appearance from the Patriot Guard Riders, a national organization of motorcycle enthusiasts created to oppose the Westboro Baptist Church's funeral protests. They attend funerals to honor fallen military personnel.

Performances include the Kiltie Band of York, members of the Dallastown High School Marching Band, the Dallastown Area High School JROTC and soloist Tonia Grubb. Members of the York County Fire School will participate in the event.

The annual Supreme Sacrifice observance will be conducted, with official posting of the colors by the York County Sheriff's Honor Guard and York County Veterans Honor Guard.

A dove release was organized by Vietnam veteran Bill Duerr Jr., and a medical helicopter will be displayed in honor of emergency personnel, Sommer said.

The military address will be delivered by Brig. Gen. Gerald E. Otterbein, commander of the 193rd Special Operations Wing, Pennsylvania Air National Guard in Middletown.

State Rep. Keith Gillespie, R-Springettsbury Township, will speak on behalf of fire and police officials.

The Court of Valor is a granite archway topped with a piece of steel from the World Trade Center. The monument was unveiled in 2009, and its granite columns bear the names of people awarded medals for valor and sacrifice. Eighteen more names will be added this year, for a total of 297.

The ceremony starts at 1 p.m. at the cemetery, 700 N. George St., and will be held in the veterans section, most easily accessible from the Pennsylvania Avenue entrance.

-- Reach Christina Kauffman at ckauffman@yorkdispatch.com.