There's a full menu of activity on the table this weekend for the Washington area's Civil War and regional history buffs. Activities include what is billed as an authentic -- if nonlethal -- reenactment of the Battle of First Manassas, as the Confederates called it, or the first Battle of Bull Run, as the Union side called it.

Either way, the original battle in 1861, a scant 40 miles from the U.S. Capitol, was a rout of the North by southern troops that the Rebels did not capitalize upon.

Washington, then lightly defended, could have fallen into Confederate hands, but the Stars and Stripes still waved.

In addition to the reenactment, the Prince William County Park Authority and the Manassas City Museum, among others, are scheduling separate events in observance of the anniversary.

Here's a rundown:The American Civil War Commemorative Committee, a private group based in Culpeper, Va., is sponsoring the battle reenactment, although not on the actual battlefield, where the centennial reenactment was done in 1961.

This Sunday's program will feature about 5,000 authentically uniformed and equipped "soldiers" in a battle to be simulated starting at 1 p.m. on the Westfields tract, off Rte. 28 between Rte. 50 and I-66 in western Fairfax County.

It's two miles from the real battlefield site. Hollywood-style pyrotechnics are promised.

Tickets cost up to $3, available from Ticket Center and others. Call 522-8594 for information.

In conjunction, the participants' camps will be open without charge between 9 a.m. and 9 p.m. Saturday and from 8 a.m. to 6 p.m. Sunday. The Prince William parks people and an outfit called Friends of Virginia Civil War Parks have a long list of separate activities over the weekend, centering on the original battlefield, which is now a national park.

They start with a U.S. Army twilight tattoo -- a drum and bugle ceremony -- tomorrow and resume at 9 a.m. Saturday with the Army Band playing Civil War-era music. An all-day program is in store, highlighted by a concert by the Stonewall Brigade Reenactment Band of Staunton, Va., at 3 p.m. Saturday. A "grand review" by several bands including the Stonewall (with a $2.50 adult admission charge) is scheduled for Saturday evening at the Park Authority's Ben Lomond District Park. Otherwise there will be a re-created Civil War field hospital, artillery firing demonstrations, carriage rides and guided tours.

One of the most affecting events of the weekend should be the City of Manassas' re-creation of the 1911 Peace Jubilee, which featured a reunion of Confederate and Union soldiers on the 50th anniversary of the battle. The reenactment will include appearances by several elderly ladies who served as "peace maidens" in the 1911 event. It's at 4 p.m. in the center of Manassas.

For information about the Park Authority events, Washington area residents may call a direct line, 631-2525. For word on various other battlefield events, call (703) 754-7107.