An early image of Fort Pitt is returning to Pittsburgh's Point just in time for the 250th anniversary of the city's birth.

The Fort Pitt Museum has acquired an 18th-century powder horn decorated with an outline of the five-sided fortification the British built at the Forks of the Ohio.

The powder horn will go on display Friday at the museum in Point State Park.

The state museum, built on the site of one of Fort Pitt's bastions, will be at the center of several upcoming events linked to the city's anniversary.

Friday is Light Up Night, the start of the holiday season, and the museum will have extended hours that evening. From 5 to 9 p.m. visitors can mingle with craftspeople, artists, musicians and re-enactors dressed in period clothing.

The following morning, the museum will be the site of a final "Hinge of History" seminar. The focus of the daylong event will be Gen. John Forbes. He led the British and Colonial army that forced the French to abandon and burn Fort Duquesne in November 1758.

Tuesday, Nov. 25, is the 250th anniversary of the date when Forbes arrived at the smoking ruins of the French outpost. Fort Pitt Museum, which ordinarily is closed on Mondays and Tuesdays, will be open 9 a.m. to 5 p.m. that day for a celebration that includes cake for all visitors.

The powder horn is a birthday gift from the Fort Pitt Associates, a volunteer organization of museum supporters, and Gordon Barlow, a Virginia resident who is a member of its board. Experts believe it was made sometime before 1792, when the fort was dismantled and its materials recycled into other structures in the wilderness.

To a hunter or farmer on the Pennsylvania frontier, a powder horn was his second most important possession after his rifle, according to Donn Neal, president of the associates.

"The carver saw the fort as having central importance to the new civilization being created here in Western Pennsylvania," he said.

When the horn goes on display in the museum this week, the figures etched on it will offer visitors a firsthand, contemporary account of Pittsburgh's earliest days, he said.

While the question of who made the object still is being researched, museum administrator Chuck Smith said experts are confident it was produced at or near Fort Pitt in the late 18th century.

In addition to the outline of the fort, the horn has been engraved with a British lion and unicorn and a crude map of places along Forbes Road. That was the name given to the route that Forbes' army carved through the Pennsylvania wilderness.

Spelling was idiosyncratic, Mr. Smith said. Towns and geographic features on the horn include the Alegania, or Allegheny, river and settlements at Badford, or Bedford, and Litelton, or Fort Littleton.

Army historian Douglas Cubbison, author of a new book on the Forbes campaign, will be one of the main speakers at Saturday's "Hinge of History" seminar. His book, called "Mountains, Wagons and Whiskey," will be published next month by Heritage Books.

Forbes made his march across Pennsylvania a little more than three years after another British general, Edward Braddock, was killed and his army destroyed in a disastrous effort to conquer Fort Duquesne.

"Forbes ran a model campaign," Mr. Cubbison said in an interview. "He had a well-established plan, with everything worked out in advance in his mind, and he stuck with that plan."

Forbes rejected heavy lobbying from a young George Washington, urging him to follow Braddock's road through Virginia and Maryland. Taking that route would have strengthened Virginia's claims to what became southwestern Pennsylvania.

"Later in life Washington became an American who put American interests first," Mr. Cubbison said. "At 26, he is very much a Virginian."

Forbes chose instead to cut a new road across Pennsylvania, taking a more direct route that surprised the French and their Indian allies, he said.

As his army made its deliberate way west during the summer and fall of 1758, he established supply depots and fortifications across the wilderness.

Mr. Cubbison's Saturday talk will concentrate on Forbes' decisions and movements between Nov. 12 -- when the British fought off a French and Indian attack at what is now Ligonier -- and Nov. 25, when his army occupied the Point.

Saturday's seminar will end with the unveiling of a painting by John Buxton called "Washington at the Point -- 1753."

The museum will be open to the public for Light Up Night and on Nov. 25 with admission by donation.

The museum will operate with regular admission fees on Saturday. Walk-in registration at $30 per person will be available for "Hinge of History" seminar participants.

Information on all events is available by calling the museum at 412-281-9284 and at the museum Web site, www.fortpittmuseum.com.