Veteran Civil War re-enactor Louis Varnell of Tennessee can play both sides of the conflict, sometimes wearing Union blue, sometimes Confederate gray.

But picking a side for this morning's bombardment of Fort Sumter was an easy choice -- U.S. Army blue -- so he could be on the receiving end of the thunderous rebel cannon fire expected to rattle windows across Charleston Harbor early this morning and throughout the day.

"The pivotal point is Fort Sumter," Varnell said Monday, while safely ensconced inside the island fortress's thick walls. "There is no question which one I was going to choose."

Varnell and some of the two-dozen Union re-enactors camped inside the fort this week say their assignment is akin to holding a winning lottery ticket. Of the thousands of Civil War re-enactors active in the U.S., these selected few will watch the re-created battle unfold by seeing and hearing the cannon flashes and booms that Union Maj. Robert Anderson and his defenders encountered in 1861.

The main difference from the 1861 men? "The added comfort of knowing there isn't a projectile following and that I'd have to run for cover," Varnell said.

Several of the men camped at the fort Monday absolutely refused to break character ahead of today's bombardment. Mark Silas Tackitt of Seattle, who is playing Anderson, even had a man dressed as Confederate "sympathizer" tossed from the fort at musket point until he removed a Jefferson Davis button from his lapel.

Moments later, Tackitt repeated the Union's pre-war point of view: that any differences with the South must be settled in "Washington City, not under force of arms."

He added that he still considered the Union whole up to that point, and that none of the 33 stars from the giant American flag of 1861 flying above the fort had been removed. The banner is the only flag flying above the National Park Service-run site ahead of today's attack. Normally, several Confederate flags are flown there as well, to show the fort's different periods of occupation.

Other re-enactors said they were trying to make their Fort Sumter experience as real and as isolating as they can to be in line with what Anderson and his 85 men faced on April 12, albeit on a smaller scale. They brought minimal supplies, are scarce of food and sleep on brick floors.

"I'm wondering if we're ever going to get any food," said Joe Grimes, speaking as a Union soldier on guard duty. A moment later the fort's cook passed out a batch of homemade "hoe cakes" -- cornmeal fried in bacon grease that was a staple of the foot soldier.

Meanwhile, three miles across the harbor from Fort Sumter near Patriots Point in Mount Pleasant, a battery of 11 Confederate guns is set up to deliver multiple salvos in today's attack. Two rebels in charge of one of the guns also refused to break character as they talked in anticipation of finally getting to fire on the distant trapped Yankees.

"If they just surrender the fort, we wouldn't have to fire a shot," said Chuck Drye of Monroe, N.C. "We've been asking them to leave for the last three weeks."

Numerous events are planned to mark the sesquicentennial of the Civil War, which began April 12, 1861, with shots fired from James Island at Union forces in Fort Sumter.

What: 'When Jesus Wept' sunrise concert, in remembrance of the moment the first shots of the Civil War were fired. Music for Brass Ensemble & Military Drums; a short candlelight concert featuring hymns by Colonial American composers including William Billings and others.

When: 4:30-5 a.m.

Where: White Point Garden

Admission: Free

What: Groups around the Charleston area fire cannons throughout the day to mark the sesquicentennial of the Civil War.

When: The commemoration starts with a 10-inch mortar cannon fired at 6:45 a.m. from Fort Johnson.

Where: The following other locations will immediately start firing after the first round for about 45 minutes. Sporadic firing will occur from these locations, and there will be another 45-minute barrage at 7:45 p.m.:

Patriots Point in Mount Pleasant

Pitt Street Bridge in Mount Pleasant

Alhambra Hall in Mount Pleasant

Breach Inlet on Sullivan's Island

Station 22 on Sullivan's Island

Fort Johnson on James Island

Carolina Yacht Club (between 7 and about 9 p.m.)

What: Inheriting the Wind: American Youth at the Onset of Battle, a lecture by James McPherson, author of the Pulitzer Prize winning 'Battle Cry of Freedom: The Civil War Era.' See www.sccivilwar.org.

When: 7 p.m.

Where: Gibbes Museum of Art

Admission: Free

Liberty Square: Special programs offered 1-5 p.m. today through Thursday.

6 a.m.: Camp opens to public

6:15 a.m.: Morning parade 'Prepare to Fire'

6:50-7 a.m.: First Barrage of Artillery Fire

7:30 a.m.: Artillery Fire

8 a.m.: Artillery Fire

9 a.m.: Artillery Fire

9:30 a.m.: Infantry Drill/Firing

10 a.m.: Artillery Fire

10:30 a.m.: Cavalry Demo

11 a.m.: Artillery Fire

Noon: Artillery Fire

1 p.m.: Artillery Fire

1:30 p.m.: Infantry Drill/ Firing

2 p.m.: Artillery Fire

3 p.m.: Artillery Fire

3:30 p.m.: Cavalry Demo

4 p.m.: Artillery Fire

5 p.m.: Artillery Fire

5:30 p.m.: Prepare for Possible Enemy Landing

6 p.m.: Artillery Fire

7 p.m.: Evening Parade

7:30 p.m.: Bombardment of Fort Sumter update

8 p.m.: Artillery barrage

8:30 p.m.: Artillery fire ends

8:45 p.m.: 97th Regimental String Band

10 p.m.: Camp closes to public

Fort Sumter

Boat departure times

Liberty Square, Charleston, 9:30 a.m., noon, 2:30 p.m., 5:15 p.m.

Patriots Point, Mount Pleasant, 10:45 a.m., 1:30 p.m., 4 p.m.

On Sunday, the last boat will depart from Liberty Square at 2:30 p.m.

Thursday: Ceremony for the surrender of Fort Sumter at 9:30 a.m., 10:45 a.m., noon, 1:30 p.m. and 2:30 p.m. Confederate soldier musket drill, firing and heavy artillery drill for the 4 p.m. and 5:15 p.m. tours.

Friday-Sunday: Confederate soldier musket drill, firing and heavy artillery drill for every boat tour.

Fort Moultrie

Fort and campsites open at 9 a.m. and the fort closes at 7 p.m.

National Park Service schedule subject to change.