A 22-year-old bicyclist was killed Wednesday night in Park City as he and his roommate were returning home after dining out.

The pair had dinner on Main Street and were biking to Prospector Avenue about 10 p.m. when the man, who was not wearing a helmet, crashed on Deer Valley Drive near Aerie Drive.

His roommate was riding ahead of him and did not see what happened, according to Park City police. The bicyclist was taken to University Hospital, where he died of his injuries.

Police say they are investigating.