FAIR HILL -- Combined driving might be considered the rugby of horse sports, or at least the marathon portion of the triathlon event.
It doesn't sound like a contact activity this unique equine competition where horses pulling a carriage and a driver negotiate some of Maryland's loveliest terrain over a 15-mile course.
But yesterday, at selection trials sponsored by the United States Equestrian Team, in which pairs of horses qualify for next year's World Championships in Gladstone, N.J., there was a steady stream of lost wheels, broken straps, twisted traces and turned over carriages.
It isn't as dangerous as it sounds.
No horses were injured, and the pileups that occur when the carriages flip over seem to happen in slow motion even though the animals are galloping at the time.
Two people, however, were taken to an area hospital after they werethrown out of carriages.
The incidents occurred on the Cecil County course at Fair Hill at a hazard called the "House of Seagram."
The horses and carriages first go through about 10 miles of brisk trotting and walking, two 10-minute rest stops and two checks by veterinarians before they start a final phase called "hazards." At Fair Hill, the last part of the marathon test consists of a 5.7-mile course with eight natural or man-made obstacles.
The hazards consist of a maze of gates that the horses negotiate through water or on hillsides or in the case of the "House of Seagram," through a barn-like edifice, surrounded by pens and decorated with whiskey barrels.
Two drivers, Tucker Johnson, a member of the U.S. gold medal team at the 1991 World Championships in Austria, and Chester Weber, 17, the youngest driver in the competition, had no problem getting through the maze. It was the exit where their troubles occurred.
"The ground was uneven, and people simply got going too fast," said Sharon Chesson, who ranks second in the Fair Hill standings after the first two days of competition.
Weber, whose parents own two of thoroughbred racing's top horses, Sultry Song and Solar Splendor, hurt his hand and was taken to the hospital after his carriage flipped over coming out of the "House of Seagram."
Weber was fourth after the first day's dressage competition, which is a more sedate affair, but he was eliminated after his spill.
Johnson said that when his carriage turned over at the same hazard, a referee that was riding in his vehicle was thrown out and hurt her hip.
But Jimmy Fairclough of Newton, N.J., had no problem with the course and moved into first place.
"You have to get a rhythm going with your horses when you enter a hazard," Fairclough said.
Most of the carriages for the marathon competition are specially made metal carts manufactured by a German company called Kunhle.
Bill Lower, driving a pair of horses owned by Bob Cook, of Mount Airy, dropped from first to third in the standings after encountering trouble at "The Silver Bullet," a beer garden filled with a tricky maze of gates.
A plank of a fence from one of the gates rammed through the wheels of his carriage after he negotiated part of the hazard. He had to maneuver his horses from the obstruction before he could go on.
"This is the first time I've driven this particular pair through hazards," Lower said. "But I'm happy with the horses. They were powerful and we ended up making all of our times."
Owner Cook, who watched for the first time from the sidelines, said he thinks he is now too old at 55 to keep driving his horses in such top-level competition.
"It is too stressful," he said. "But it also so exhilarating. It is like fox hunting, but in a carriage."
The competition ends today with obstacle driving in an arena. The horses and carriages negotiate a series of tests involving tight turns. At strategic points, there are cones placed with a tennis ball on top.
Penalties are deducted every time a horse and carriage knocks a tennis ball off the cone.