The Zodiac Killer made a payphone call near the corner of Main and Clinton Streets approximately seventy minutes after the brutal knife attack on Cecelia Shepard and Bryan Hartnell by the shores of Lake Berryessa. He uttered these words to relief police dispatcher David Slaight: "I want to report a murder, no, a double murder. They are two miles north of Park Headquarters. They were in a white Volkswagen Karmann Ghia. I'm the one that did it". It always seemed odd that the Zodiac Killer could be so wide of the mark concerning the distance he attributed between the crime scene and Park Headquarters, when it was only 0.7 miles. The Zodiac Killer, a man of maps and codes, surely couldn't have mistaken 0.7 miles for 2 miles driving along Knoxville Road - leading to the notion that the 2 mile attribution was accidentally inserted into his payphone message, but the distance had some significance. That significance being, that the Zodiac Killer didn't enter his vehicle at the crime scene, but further north along Knoxville Road. He may have entered his vehicle at the Smittle Creek Day Use Area which is 1.83 miles (approx 2 miles) north of Park Headquarters. When he made the payphone call he accidentally inserted the distance he traveled in his vehicle to Park Headquarters rather than from the crime scene. There were two sightings of a suspicious man at Smittle Creek to back up this very notion. If we can place the Zodiac Killer at this location twice in one day, described by two sets of eyewitnesses, then we may be in business.
The white circle on Knoxville Road below (as the crow flies) is exactly 0.8 miles north from the vehicle of Bryan Hartnell and exactly 2 miles north of 5100 Knoxville Road (A&W Root Beer stand). This is extremely important because the police report stated that the three women who spotted a suspicious man observing them from the hillside "parked their vehicle at a location two miles north of the A & W Root Beer stand on Knoxville Road". This was followed by a second suspicious sighting of a man by Dr Rayfield & Son just over 2 hours later. They described a "white male adult subject walking in the area, about 5'10", heavy build, wearing dark trousers, a dark shirt with red in it, long sleeves". This sighting likely after the attack on the young couple and described in the police report as a "location approximately 8/10ths of a mile from the scene of the victim's vehicle". Two sightings in the identical area, alongside Smittle Creek Trailhead.
The white circle on Knoxville Road below (as the crow flies) is exactly 0.8 miles north from the vehicle of Bryan Hartnell and exactly 2 miles north of 5100 Knoxville Road (A&W Root Beer stand). This is extremely important because the police report stated that the three women who spotted a suspicious man observing them from the hillside "parked their vehicle at a location two miles north of the A & W Root Beer stand on Knoxville Road". This was followed by a second suspicious sighting of a man by Dr Rayfield & Son just over 2 hours later. They described a "white male adult subject walking in the area, about 5'10", heavy build, wearing dark trousers, a dark shirt with red in it, long sleeves". This sighting likely after the attack on the young couple and described in the police report as a "location approximately 8/10ths of a mile from the scene of the victim's vehicle". Two sightings in the identical area, alongside Smittle Creek Trailhead.
There is every chance that this was the Zodiac Killer, who had originally targeted the three female students of Pacific Union College, before aborting his attack and later settling on Bryan Hartnell and Cecelia Shepard only 0.8 miles south. The man stalking the hillside while the girls were sunbathing eventually retreated for whatever reason, and his vehicle had vanished when the girls returned to their vehicle at approximately 4:30 pm. It is perfectly conceivable he entered his vehicle at the Smittle Creek Trailhead (shown by the yellow circle) and drove just 600 meters north to the Smittle Creek Day Use Area. He may have deemed that having his vehicle in such close proximity to a triple murder was probably not the wisest move, and relocated it several hundred meters up the road to provide a cautionary 'buffer zone'. Whether his intention was to return a short while later to complete his mission cannot be ascertained, because the girls had thwarted any intentions by leaving shortly after.
If the Zodiac Killer had parked at the Smittle Creek Day Use Area, left it there, and trawled the hillsides of Lake Berryessa traveling south, while looking for potential victims, then on his return from the attack on Bryan Hartnell and Cecelia Shepard he would have to pass by Dr Rayfield & Son at Smittle Creek Trailhead to reach his vehicle. That is why they spotted a suspicious man traveling across the upper reaches of the hillside sometime after 6:30 pm, wearing a shirt with red in it. The Zodiac Killer traveled a further 600 meters to the Smittle Creek Day Use Area, got in his vehicle and drove 1.83 miles south along Knoxville Road past the Park Headquarters. When he reached the payphone at Napa he mistakenly described this distance of 1.83 miles as "two miles north of Park Headquarters", accidentally giving away the location of where he parked his vehicle on September 27th 1969. Or maybe he was just terrible at distances - but great at cryptograms, codes, maps and radians. We all have to be bad at something.
If the Zodiac Killer had parked at the Smittle Creek Day Use Area, left it there, and trawled the hillsides of Lake Berryessa traveling south, while looking for potential victims, then on his return from the attack on Bryan Hartnell and Cecelia Shepard he would have to pass by Dr Rayfield & Son at Smittle Creek Trailhead to reach his vehicle. That is why they spotted a suspicious man traveling across the upper reaches of the hillside sometime after 6:30 pm, wearing a shirt with red in it. The Zodiac Killer traveled a further 600 meters to the Smittle Creek Day Use Area, got in his vehicle and drove 1.83 miles south along Knoxville Road past the Park Headquarters. When he reached the payphone at Napa he mistakenly described this distance of 1.83 miles as "two miles north of Park Headquarters", accidentally giving away the location of where he parked his vehicle on September 27th 1969. Or maybe he was just terrible at distances - but great at cryptograms, codes, maps and radians. We all have to be bad at something.