The first murders of David Faraday and Betty Lou Jensen on December 20th 1968, just beyond the outskirts of Vallejo in an isolated turnout on Lake Herman Road, was but a short drive of 15-20 minutes from downtown Vallejo. Pierre Bidou, a police detective from the Benicia Police Department, was one of the first officers on the scene that fateful night. He stated in an interview on True Crime in 2010 that "There are no street lights here, there still isn't, when you come out here at night time and look at this place, it is dark, really dark. There was hardly anybody coming by here, if you had a car coming by every hour that would probably be a lot. And a lot of people didn't know this road, so you had to be somewhat familiar with this area".
The second attack, in another secluded area at Blue Rock Springs Park on July 4th 1969, was a four-mile journey northwest of Lake Herman Road, and a 15 minute drive from downtown Vallejo. On this occasion Michael Mageau survived, but unfortunately Darlene Ferrin became the Zodiac Killer's third fatality. This time though, the killer was more brazen, calling police dispatcher Nancy Slover from a phone booth at the gas station at Springs Road and Tuolumne, just a short 10 minute drive from the crime scene. The attack occurred around midnight, with the call logged at 12:40 am. This left 40 minutes of unaccounted time to be explained, leading to the notion of a killer who returned home first to dispose of any incriminating evidence, including his weapon and possibly clothes, before venturing back out with renewed confidence and placing the call. This unexplained time could lend greater weight to the theory that the killer was a local to the area of Vallejo, combined with his apparent knowledge of the Lake Herman Road and Blue Rock Springs Park areas.
The third attack at Lake Berryessa, with a driving time of approximately 1 hour and 20 minutes, saw the killer venture further away from the Vallejo area, if indeed he resided there. The male victim, Bryan Hartnell, would again survive, however, the devastating ten knife injuries sustained by Cecelia Shepard would sadly claim her life just two days later at the Queen of the Valley Hospital. The attack took place early evening on September 27th 1969 at around 6:30 pm, with the killer leaving a message at the scene of the crime on the car door of Bryan Hartnell's vehicle. If we take the message written on Bryan Hartnell's Volkswagen Karmann Ghia door with near accuracy, then the 27 mile journey to the payphone at 1231 Main Street, Napa away from Lake Berryessa, would have taken approximately 50 minutes. The phone call was logged at 7:40 pm, leaving a shortfall of 20 minutes. http://www.zodiacciphers.com/zodiac-news/lake-berryessa-north-of-the-crime-scene-pt2.
Napa County is a direct route between Vallejo and Lake Berryessa, so if the killer lived in, or very close to Vallejo, he would have left himself approximately 25-30 minutes to arrive home, after placing the phone call.
The Zodiac Killer's last confirmed murder was that of Paul Stine, on October 11th 1969, leading people to consider the possibility the killer may have been a resident of San Francisco or the Presidio Heights area, bearing in mind his first 14 confirmed letters and cards were postmarked San Francisco, starting with the July 31st 1969 mailings and ending with the Halloween Card. But bearing in mind his apparent knowledge of the first two crime scene locations, that a resident of San Francisco would unlikely possess (unless a former resident), it is quite plausible he lived somewhere in the region of Vallejo and mailed his letters en route to his place of work in San Francisco. The third option being, he at one time had lived at both locations.
The lost 40 minutes after the Blue Rock Springs attack is noteworthy though, in that, did the killer drive home first and remove any incriminating evidence, before driving back to the gas station at Springs Road and Tuolumne - or more logically as Mike Morford suggested on Zodiackillersite forum - walk back to the payphone to place the first phone call, thereby attracting less attention to himself? Quote "I personally think Zodiac lived close to that phonebooth on Springs & Tuolumne, went home, and stashed his gun and car, and walked to the phonebooth. With no car, he was less likely to be noticed". If indeed this was the case - and taking into account the time it took him to change, check for any transference from the crime scene, stash the gun and ready himself before venturing back to the payphone - this may have left him with about 15 minutes surplus traveling time, to walk back and make the phone call, thereby placing the Zodiac Killer's residence extremely close to the corner of Springs Road and Tuolumne (in distance terms, a one mile radius of the payphone).
In the August 4th 1969 Debut of Zodiac letter, the author wrote "The man who told police that my car was brown was a negro about 40-45 rather shabbly dressed. I was in this phone booth having some fun with the Vallejo cop when he was walking by. When I hung the phone up the damn thing began to ring & that drew his attention to me + my car". This seemed to suggest he was still using his vehicle at that point, yet it could have been an employed diversion, so as not to expose the close proximity of his home address - with the apparent over emphasis on the wording "me + my car" used to sell us a story, when he quite simply could have said "When I hung the phone up the damn thing began to ring & that drew his attention to me".
This takes into account the applying of logic to the mind of a serial killer, who may in time be found to have been responsible for 37 murders or more over a five-year period. Therefore, you can possibly disregard everything you have just read as sheer madness.
Incidentally, Arthur Leigh Allen was living within this one mile radius at 32 Fresno Street during the first two confirmed attacks at Lake Herman Road and Blue Rock Springs Park. His residence sits approximately 10 minutes north of the Springs Road and Tuolumne Street intersection.