ACADIA NATIONAL PARK – A man from Washington state who died over the weekend while bicycling on Park Loop Road broke his spinal cord when he struck a locked gate, according to a park ranger.

Stephen Kennedy, 63, of Washouga, Wash., and his son Andrew Kennedy, 34, who lives on Mount Desert Island, had started bicycling on Park Loop Road at the Cadillac Mountain entrance and were headed counterclockwise on the road when the accident occurred around 3:45 p.m. Saturday, Acadia National Park Ranger Stuart West said Monday.

Most of the circular road, when all of it is open to vehicular traffic in the summer, allows only one-way traffic in a clockwise direction. In the winter, most of the road is closed to vehicular traffic, except for a short section between Seal Harbor and Jordan Pond and another section between Schooner Head Road and Otter Cliffs Road.

The men already had maneuvered past two locked gates on the road when Stephen Kennedy hit the third one that he and his son encountered, the ranger said.

Andrew Kennedy stopped quickly when he came upon the gate near the intersection of Park Loop Road and Otter Cliffs Road, but his father passed him, according to West. The elder Kennedy slammed on his brakes and flipped over the bicycle handlebars, the ranger said.

“He went airborne and hit the gate in an upside down position,” West said. The accident snapped Kennedy’s spinal cord, he said.

Both men were wearing helmets at the time, according to the ranger. Stephen Kennedy was pronounced dead later Saturday after being taken by ambulance to Mount Desert Island Hospital in Bar Harbor, he said.

West said bicycling against the flow of oncoming cars and trucks is prohibited on Park Loop Road. Because use of the closed sections of the road in the winter is relatively light, he said, the one-way regulation on those sections generally is not enforced.

The ranger said that, as in all serious accidents, park officials will review what happened to determine what, if anything, could be done to prevent possible similar incidents.

West said bicyclists always should use proper safety equipment when bicycling in the park and should exercise caution when on roads with which they are unfamiliar.