The three girls from Pacific Union College "parked their vehicle at a location two miles north of the A & W Root Beer stand on Knoxville Road". The Sugar Loaf Park A & W was situated at 5100 Knoxville Road. They would have parked their vehicle somewhere in or between the region of Smittle Creek Trailhead and Smittle Creek Day Use Area. They arrived at 3:30 pm. "After approximately one-half hour had passed (4:00 pm), they observed what appeared to be the same subject standing with 40 or 50 feet of them, apparently observing them. The subject hung around the area for approximately 45 minutes (4:45 pm) and then the girls observed him walk up the hill". Allowing 10 minutes for the girls to get their belongings from their vehicle and walk to the beach, the total time passed would have the man walking up the hill at around 4:55 pm (approximately 5:00 pm). However, one page later in the police report, it stated "The three girls left the area about 4:30 pm and the subject's vehicle was gone". Therefore, we have to estimate the man left that location sometime between 4:30 pm and 5:00 pm. This is the approximate area that John and Marilyn were parked up at 5:15 pm when they spotted Bryan and Cecelia heading south to the area of the crime scene. If the man spotted by the three girls was the Zodiac Killer, it is clear that Bryan Hartnell and Cecelia Shepard were not trailed by their eventual attacker from St Helena.
Is it a coincidence that just a short time later, Dr. Rayfield and his son observed a "white male adult subject walking in the area of Smittle Creek, described as about 5'10", heavy build, wearing dark trousers, a dark shirt with red in it, long sleeves. Dr Rayfield and his son stated that they did not notice a vehicle in the area of their vehicle and only this subject at a distance of about 100 yards. This location was approximately 8/10ths of a mile from the scene of the victim's vehicle. There are four coves of water between the scene of the crime and the area where the doctor saw the subject". They stated that they parked their vehicle at about 6:30 pm that evening and walked down to the beach, when they noticed the man approximately 100 yards away. If this was around 6:40 pm, we have a small discrepancy of about 10 minutes for a man to walk from the crime scene to Smittle Creek. An attack on Bryan Hartnell and Cecelia Shepard slightly earlier, or Dr. Rayfield's time estimate a few minutes off, could easily account for this. A suspicious character noted by two sets of eyewitnesses 0.8 miles north of the crime scene, before and after the attack on Bryan Hartnell and Cecelia Shepard. Was this man the Zodiac Killer, trawling the hillsides of Lake Berryessa on foot looking for potential victims, before returning to his vehicle parked somewhere in the region of Smittle Creek?