GETTYSBURG, Pa. - An opening volley of musket fire ushered in the start of the milestone commemoration of the Battle of Gettysburg on Friday, 150 years after the Union Army turned away a Confederate advance in the pivotal conflict of the American Civil War.

Wearing period uniforms, thousands of Civil War buffs gathered on a private farm outside the actual battlefield to take part in the battle re-enactment considered the pinnacle of the hobby. The sights and sounds of faux warfare are also a big draw for visitors - about 200,000 people are expected to descend on the small, south-central Pennsylvania town during a 10-day period that started Friday.

"Troops moved correctly, scenarios were done as designed, with only a few flaws," Terry Shelton, the Confederate "commander" said in a confident voice befitting of a general. "There was a lot of planning."

It was one of two re-enactments planned to commemorate Gettysburg, the war's bloodiest conflict with up to 10,000 killed and 30,000 wounded July 1-3, 1863. The National Park Service's official ceremonies begin Sunday.

The events are years in the making after being jointly planned by the Park Service and a host of community organizers and volunteers. It's a lot of work to welcome hundreds of thousands of visitors to a town of 7,500 people.

The Gettysburg Convention and Visitors Bureau set up five temporary welcome tents around town in addition to its two permanent facilities. Satellite parking areas and shuttle bus service are in place for the expected crush of drivers. Cellphone coverage is expanded to accommodate social media enthusiasts.

And don't forget the portable toilets.

"There are literally hundreds in this community," said visitors bureau vice president Stacey Fox.

So far, so good.

"Today, Day 1, seems to be going off very, very well," Fox said. "Everyone seems to be happy."

The Blue-Gray Alliance re-enactment group opened the schedule Friday with its first of three days of battle re-creations. Organizers expected about 10,000 participants to take part.

They began with a detailed, three-hour re-enactment of the battle's first day, when Union cavalry looking for the enemy encountered Confederate infantry. Other re-enactors took part in living history presentations, such as the demonstration of a Confederate field hospital at the Daniel Lady Farm.

Across the street, in a field doubling as the parking lot, Michael Sipes took care of his brown horse, Dale, before pulling on his gray wool cavalry topcoat to get lunch. He's portraying Confederate Lt. Gen. Jubal Early - it says so on his business card. Sipes, 61, a gun shop owner from Hanover, does living history appearances regularly, too.

First, though, he had to finish a chore.

"Who thought a general would be cleaning up his own horses," he asked while shoveling waste out of the trailer.

Sipes, a descendant of a Confederate veteran, said he prefers smaller-scale re-enactments, though welcomes the opportunity at Gettysburg this year to teach history.

"If you don't know your past, you won't know your future," he said. "If you forget about your past and you don't know where you came from, you won't know where you're going."

Wearing a white smock over his dark vest and white dress shirt, Henry Trippe relished his role as a Civil War surgeon and answering questions about treating injuries and amputations.

Trippe, 59, a sales clerk from Ypsilanti, Mich., brought his own collection of scalpels, knives and anesthetics including powdered morphine.

Or at least, white power made to look like morphine.

"I do not have a drug permit," he joked to visitors. "Do not report me to drug enforcement."

The Park Service programs begin with a Sunday night ceremony. Another re-enactment held by the Gettysburg Anniversary Committee is scheduled on a farm north of town July 4-7. Re-enactments are held on private properties.