 In 1978, the Barrenjoey Road area came to national attention due to the unsolved disappearance of Trudie Adams.From the southern junction in Mona Vale with Pittwater Road, Barrenjoey Road has 6 traffic lanes north to Newport.From here through to the northern termination point on the Pacific Ocean side of Palm Beach, the road is generally only 2 lanes wide, with the exception of a few kilometres in north Avalon/south Palm Beach where it is 4 traffic lanes wide.