On Sept. 14, 1862, Richard Smith, 19, and his brother James, 17, my grandfather's uncles, were racing up the slopes of South Mountain with the rest of the 35th New York Infantry Regiment.

The Union 1st Corps under Maj. Gen. Joseph Hooker was ordered into the mountain gaps to surprise Robert E. Lee's Army of Northern Virginia before it could regroup during its march into Maryland.

Unfortunately for them, the 35th didn't get through and great-great-uncle Richard got himself shot. Three days later, the two massive armies clashed at the Battle of Antietam -- the bloodiest single day in American history.

More than 23,000 men were killed, wounded or couldn't be accounted for.

I haven't found proof of it yet, but it seems likely that great-great-uncle James fought and survived that most terrible of days. The 35th was part of Brig. Gen. Marsena Patrick's 3rd Brigade, all New Yorkers, who clashed with the Stonewall Brigade and Hampton's Legion of South Carolina in some of the worst of the fighting.

Just over 145 years later -- on Dec. 1 -- my brother-in-law John Miglarese and I walked the eerily silent fields of Antietam.

A narrow blacktop drive roughly borders the line where the attacking Union Army clashed with the Confederate defenses.

There are monuments to Union regiments to the north and east of that modern line of demarcation, and Confederate markers to the south and west -- the cold stones facing one another across the little road just as those desperate men had faced each other during those 12 terrible hours.

We stood by the cornfield where more than 13,000 fell between dawn and 10 in the morning, the place where Gen. Patrick's New Yorkers had been in the center of the maelstrom.

We walked along the sunken road, called Bloody Lane by the soldiers, where the fight raged during midday, and we stood above the dominant Confederate positions at "Burnside's Bridge," where fewer than 1,000 held off half an army until late in the day.

Riding home, we wished we could return the next night for the park's annual luminaria demonstration, when a candle is lit on the field for every casualty suffered at Antietam.

"It is difficult to understand the enormity of 23,000 casualties in one day," our park guide had told us. "But seeing 23,000 candles burning, and then burning out, fills you with some understanding of what happened here that day."

Steven D. Hale is an Aiken freelance writer and community activist.