The young couple came up the trail from the C&O Canal in the early hours of the morning, she carrying a blanket and he a beer cooler and both wearing dazed expressions.

"What the hell is going on?" the young man said. "Is this some kind of race?"

No, explained one of the sweat-drenched hikers who had disturbed the couple's peace, this was just the finish of the Sierra Club's annual 100-kilometer hike from Georgetown to Harpers Ferry.

"In the middle of the night?" the young woman asked.

"Well. yes," a Sierra Clubber said. "We start in Washington at 3 o'clock in the morning and we hike for maybe 24 hours."

The young man shook his head. "Weird," he said.

"Well, it's, uh, more peaceful this way," the hiker said, lamely as he staggered up Sandy Hook Road to the American Youth Hostel, where showers, food and a bunk were waiting.

"Why?" someone asked Sue McElfresh, an eighth-grade math teacher at Robinson High School in Fairfax, when she began the hike between rain showers Saturday morning.

"Why not?" McElfresh said, and strode off into the mist.

Cosponsor Loren Friesen, an attorney with the Federal Home Loan Board, had no better explanation for the fourth annual hike, which he and Ray Martin have taken pains to make sure will never become a media event.

"It exhibits the strong lure of the tow path, our own folly, or both," he said. He said this early on. At the end he still was smiling, but it was sort of a fixed grin on a gray face.

About half the starters usually finish, and by 3 a.m. Sunday a score or so of the 46 had arrived. Others had packed it in at one of the four food stops manned by volunteers who had sympathy for, but less hubris than, the hikers. One or two had simply vanished, "but I'm sure they'll turn up," Friesen said. "We haven't lost anybody yet."

The affair is noncompetitive, but for the record, Paul Robertson, 37, of Oxon Hill, did the 62 miles in 12:55:40, almost three hours ahead of the next finisher, Jonathan Acton of Baltimore. Somebody said that probably was a record, "except that we don't keep records."

The spirit of the event was demonstrated by Ben Sherman, 53, of McLean, and Steve Marby, 22, of Gap, Pa., who strolled in together and took pains to record identical times of 17:37.0. The senior starter was Ed Garvey, 62, of the Potomac Appalachian Trail Club, who took about 22 hours. He had tuned up with a 12-hour, 40-mile stroll the week before.

Everbody was pulling for Kurt Howell, 9, who was said to have passed mile post 52 near Cacoctin Creek, after his father and older brother had pooped out, but it was not known whether he made it.

"Was it worth it?" a young woman was asked as her blistered feet were managed at the hostel. "How about those glow worms/" She said. "I didn't even need my flashlight most of the time."