On October 11th 1969 Paul Stine was callously murdered, execution style in his taxicab, before the killer exited the scene, heading north into the darkness along Cherry Street. A short time later police officer Donald Fouke and his partner Eric Zelms received a radio broadcast of a possible assault and robbery adjacent to 3898 Washington Street and were making their approach towards the intersection of Jackson and Maple Street. The police officers and the Zodiac Killer were on a collision course, however on this occasion the resulting impact would leave barely a ripple, as the possible killer, observed by the two officers, was able to continue his journey unhindered. The mistake had been made, the possibility of capturing the Zodiac Killer had gone, and the murderer of five has never been seen since. All that remained was the physical description of the suspect given by Donald Fouke, in addition to his walking style, described as a 'lumbering gait, sort of stumbling along, like a semi-limp'.    

If the Zodiac Killer prior to this crime had experienced any difficulty in walking, it may have seemed foolhardy at best to have committed this crime in a heavily populated area, where his escape route necessitated exiting the scene of the crime by foot. Any sort of injury could have been the difference between freedom or capture, however as it turned out, the hand of fortune was once again on our killer's side.
http://www.zodiacciphers.com/zodiac-news/presidio-heights-revisited.
In the above article we examined the murderer's claim in the October 13th 1969 Paul Stine letter, where he stated "I am the murderer of the taxi driver over by Washington St + Maple St last night, to prove this here is a blood stained piece of his shirt." It considered a possibility that the murder took place at the Washington and Maple Street intersection, and examined the reasoning behind the murderer wiping down the external driver side door of the taxicab, why he was wiping down the driver side compartment area and more importantly how the murderer possibly received the injury, described by Donald Fouke as a 'semi-limp'.
The only reason to have touched the driver side door of the taxicab or its adjoining panel, was that he either leaned on it after he summoned the taxicab at the Mason and Geary intersection and spoke to Paul Stine, or he actually opened the driver side door to gain access to the vehicle. The first option seems unlikely, knowing that in a matter of minutes he is about to put a gun to the head of the taxicab driver and brutally execute him, so leaving fingerprints in advance on a door, he later has to waste time removing after the murder seems unnecessary. Therefore one could conclude that touching the driver side door handle was most likely forced upon him by circumstance.  
The premise was that the Zodiac Killer committed the murder at Washington and Maple Street, but his initial plans were forfeited when the taxicab, not placed in park by Paul Stine, as he was on a 'run through', motioned forward out of control. The Zodiac Killer's plan of removing items from the victim, particularly the portion of Paul Stine's shirt, to mail to the San Francisco Chronicle, was now in jeopardy. Literally thinking on his feet, the murderer quickly exited the moving vehicle by the left rear door and entered the driver side door, stepped over the lifeless body of Paul Stine, possibly bracing himself against the front compartment for support, he then pushed against the left side of Paul Stine, to access the vehicle pedals and coasted the taxicab to the intersection of Washington and Cherry. This covers all the bases; the claim by the Zodiac Killer that the murder took place at Washington and Maple, along with his necessity to wipe both the external driver side door and internal driver side compartment area. This would also explain the blood pattern on Paul Stine's shirt, that suggests the victim was upright for a measurable period of time and did not slump over immediately to a horizontal position.

Exiting the moving vehicle may have injured his ankle as his foot planted or jarred on the roadside, or quite possibly he may have aggravated a previous injury. This could explain his unhurried exit north along Cherry Street and the 'lumbering gait, sort of stumbling along, like a semi-limp', described by Donald Fouke.
Two weeks prior to this murder, on September 27th 1969, Bryan Hartnell and Cecelia Shepard were savagely attacked along the shoreline of Lake Berryessa.
Prior to the attack, three girls sunbathing noticed a man approximately 50 feet away observing them sunbathing. Their perception was that each time they looked at him he evaded eye contact, thus drawing suspicion. He was described as being between 28 and 40 years, 200 - 225 pounds, 6 feet tall, styled black hair, with rounded eyes and thin lips, was good looking, with a muscular or stocky build, wearing dark pants and a dark pullover shirt. He remained observing them, by their accounts, for between 30 - 45 minutes.    
But in a curious observation, one of the girls thought he was wearing a white belt around his back, or that it could possibly have been a tee shirt hanging out. Another stated he was wearing a black short sleeved sweater shirt bunched up at the front and a white tee shirt hanging out the back. In the article 'The Hanging Tee Shirt', it became a vague possibility that what they actually saw, was neither a belt or a shirt, but the clothesline ready and primed for an impending attack. On page 396 of Robert Graysmith's 'Zodiac Unmasked', one of the girls recalled the suspicious character, stating "I wouldn't say he had a limp, but he favored one leg when he walked". 
Later it was discovered that the assailant at Lake Berryessa had deposited ten and one half Wing-Walker shoe impressions to and from the crime scene. Wing-Walkers and Jump boots are designed for ankle support, favored by the military. Was this indicative of Zodiac having a military connection, or nothing more than a man who chose this style of footwear to protect and support a long standing foot or ankle complaint, that came under close examination, as he exited the moving vehicle at Washington and Maple, in pursuit of the trophies he was so determined to secure.

The Halloween Card was mailed on October 27th 1970, one month after of the first Lake Berryessa anniversary, and one cannot help thinking the Zodiac Killer may have delayed this correspondence a short time, with Halloween providing the perfect backdrop to 'commemorate' his attack on Bryan Hartnell and Cecelia Shepard on the shores of Lake Berryessa, bearing in mind that dressing up in costumes is central to the All Hallows Eve festivities. Before the attack on the couple, Cecelia Shepard noticed the eventual assailant conceal himself behind a tree, before approaching them bedecked in his executioner's costume. It has not gone unnoticed that the Halloween card parallels this to some extent, with eyes peering from the tree and the phrase 'peek-a-boo you are doomed' circled around a knothole in the tree, along with the mask on the skeleton. The author of the card accentuates the section 'ME' of 'DOOMED', lending weight to the thought he was indeed referring to himself as the eyes behind the tree.

The Lamplighters, hailed as one of the oldest company's in the Bay Area, specializing in Gilbert and Sullivan comic operas, operated at the Harding Theater throughout the 1960s, and were performing the Mikado in San Francisco in 1969, opening on April 20th. This connection is nothing new, with many speculating the Zodiac Killer could have been a cast member or had viewed the production, prior to his version, when he tabled in the 'Little List' letter on July 26th 1970. But it is equally likely he may have been a theater technician, employed in the area of stage management, lighting, electrics or quite possibly wardrobe, trained in costume design, as a tailor or more specifically wardrobe crafts involving masks and disguises.

In two other correspondences mailed by the Zodiac Killer he referenced three portions of Gilbert and Sullivan's The Mikado. In the 'Little List' letter mailed on July 26th 1970 he paraphrases 'A more humane Mikado' and 'As some day it may happen'. On the Exorcist letter mailed on January 29th 1974 he refers to 'On a tree by a river', in what many believe to be the Zodiac Killer's final offering. But there could be a fourth reference to the Mikado production and we need look no further than the Halloween card itself, with two possibilities.
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In 1888 Jack the Ripper terrorized the Whitechapel district of London. In the same year of somewhat less significance Ed J. Smith wrote a stage parody called The Capitalist; or, The City of Fort Worth. Designed to encourage capital investment in Fort Worth, Texas, and underwritten by local banks and railroad lines, the two act piece features characters named Yankee-Doo, Kokonut, By-Gum and Peek-A-Boo. Taken from Wikipedia. This drew its inspiration from the the Gilbert and Sullivan opera, however, it may be pushing the boat out a little farther than necessary to suggest the Zodiac Killer was either aware, or in any way influenced by this promotion.

One thing evident throughout his correspondence, was his use of the word 'shall', leading to speculation that he may have been of British origin, as the word 'shall' is infrequently used in American English. However, another option exists. As a member of theater production, his exposure to the word 'shall' would have been far more common in the performance of stage plays, particularly in traditional works of English origin, yet he would seek maximum impact when he took it to the next level and started crafting his own scripts.

Peek-a-boo is known as Peep-bo in British culture, being the act of concealing one's face behind the hands or other object, before suddenly appearing back into view and uttering the words peek-a-boo or peep-bo. It can be seen in Wikipedia that many variations involve trees, similar to the depiction on the Halloween card, where 'Hiding behind that tree' is added. See here. Whether or not this a significant phrase to the Zodiac Killer is open to question, but Peep-Bo is a character that features during Act I of the Mikado. Peep-bo can also be reversed to Bo-peep, believed to originate from the 16th century practice of concealment, before reappearing to startle or surprise. See here.   

Little Bo Peep is a popular English nursery rhyme The earliest record of this rhyme is in a manuscript of around 1805, which contains only the first verse. There are references to a children's game called "Bo-Peep", from the 16th century, including one in Shakespeare's King Lear (Act I Scene iv), but little evidence that the rhyme existed. The additional verses are first recorded in the earliest printed version in a version of Gammer Gurton's Garland or The Nursery Parnassus in 1810. 

​The phrase "to play bo peep" was in use from the 14th century to refer to the punishment of being stood in a pillory. For example, in 1364, an ale-wife, Alice Causton, was convicted of giving short measure, for which crime she had to "play bo pepe thorowe a pillery". Andrew Boorde uses the same phrase in 1542, "And evyll bakers, the which doth nat make good breade of whete, but wyl myngle other corne with whete, or do nat order and seson hit, gyving good wegght, I would they myghte play bo pepe throwe a pyllery". Taken from Wikipedia.

Little Bo Peep was a shepherdess, who lost her sheep and went in search to find them. The connection of shepherd to the Lake Berryessa attack via this route would be one hell of a stretch, however, the connection to the theater, with an English slant, still remains an avenue for investigation.

The Zodiac crimes have been analyzed extensively, almost to the point of now being questioned whether any or each of the attacks are related to one another - and this is not difficult to do. To play devil's advocate in dismantling each crime is as simple as looking for an alternative theory - which isn't necessarily a bad thing - but when the alternative theory is less likely or more outlandish than the original based on just speculation, it just provides another dark avenue to get lost within. All the Zodiac crimes are different from one another, and it is with little doubt that the murder of Paul Stine at Presidio Heights on October 11th 1969 would have been routinely dismissed as a Zodiac murder had the killer not sent a swatch of Paul Stine's shirt to the San Francisco Chronicle newspaper just two days later.

Doubts have plagued the validity of Zodiac involvement in the murder of Cecelia Shepard and attempted murder of Bryan Hartnell at Lake Berryessa on September 27th 1969, despite the fact the killer wrote on the car door of Bryan Hartnell and placed a payphone call to police dispatcher Dave Slaight just 70 minutes after leaving the crime scene. One reason touted is the failure of the murderer to identity himself as the Zodiac Killer throughout his interaction with the couple. But why should he? In all of his crimes, no doubt his intention was to leave no living eyewitnesses, so any mention to himself as being Zodiac is superfluous. Additionally, he never mentioned his pseudonym in either of his phone calls at 1231 Main Street, Napa, or the intersection of Springs Road and Tuolumne Street in Vallejo. The attack at Lake Berryessa has been further questioned regarding the handwriting on the car door of Bryan Hartnell's white 1956 Volkswagen Karmann Ghia. Was it really the Zodiac's handwriting or a copycat?      

The perpetrator at Lake Berryessa brutally stabbed Bryan Hartnell and Cecelia Shepard a total of 16 times, in what has been described a calculated and merciless attack with a long-bladed knife. The attacker had knelt over his victims while thrusting the knife down into the back of Bryan Hartnell at least six times, before turning his attention to Cecelia Shepard and stabbing her at least ten times in the back and abdomen as she was rolling around, vainly attempting to escape the onslaught. After the attack the perpetrator walked back up the hill and departed the scene.

Writing on the car door was found (see inset), believed to have been penned by the Zodiac Killer after the attack. There was no mention of any blood being detected and analyzed from the car door in any subsequent forensic examinations, however, some fingerprints were retrieved. Bryan Hartnell clearly stated in later interviews that he could not remember whether the attacker wore gloves or not. So let us examine this conundrum.
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If the killer had not wore gloves, then any fingerprints on the car door one may argue, would not have been the killer's.
He had forcefully struck both victims using a long-bladed knife at least 16 times, possibly securing them with his free hand while thrusting the knife back and forward, in what can only described as a prolonged and vicious attack. Therefore, it is practically impossible that no blood whatsoever would have transferred onto either hand. So, if the fingerprints on the car door were his, are we to believe that all the blood transferred at the scene of the horrific attack simply bypassed both his striking and accompanying hand? Or had he wiped his hands down so thoroughly after the attack that he had removed every last trace?

If he had worn gloves during the attack and leaned on the car door, blood smears would have been apparent on the vehicle but they were not. Had he worn gloves during the attack, which seemed the obvious choice from a standpoint of gripping the knife, as well as covering his fingertips, then subsequently removing them to now lean on the car door while writing the message, on the face of it seems rather illogical. He had covered his upper body with a costume to conceal his identity, so to then his expose his hands to plaster the car door with blood free fingerprints and palm prints does not sound a reasonable premise. If he wore gloves, he clearly didn't want his writing hand to smear blood onto the car door where he was trying to write, so unless he was ambidextrous, he was no doubt writing with the same hand he ferociously attacked Cecelia Shepard and Bryan Hartnell with. The same hand that was closest to any blood spatter and impact area. However, if he was ambidextrous and chose to write on the car door with his least preferred hand, then his writing may justifiably vary from the usual pattern displayed in his correspondence with the newspapers. 

There have also been question marks over the style of the handwriting itself, with certain alphabetical characters appearing incompatible with known handwriting samples from his letters. But it is evident that the handwriting on the car door is incompatible with itself.

For example, he wrote the letter 'E' three times and each one is different. He wrote the number '6' four times and each one is different. He has just stabbed a couple 16 times in a prolonged attack with his adrenaline possibly high, he was squatting or kneeling down in front of the car door parallel to his writing surface - far removed from the position he would adopt writing from the comfort of his home - he was writing above and below his natural midpoint on a cambered door, possibly faster than normal, and his lettering was larger than usual. So any comparison to his regular correspondence cannot be applied without factoring these differences into the equation.

His palm was extremely likely to have been free of contact from the car door. If it wasn't, then one would have expected blood transfer to have occurred regardless of whether the assailant was wearing gloves or not. Yes, he could have took the gloves off - but which is worse - smearing blood on the car door or placing your hands on the car door. The Zodiac Killer was undoubtedly a merciless killer, but he was certainly no fool as some would lead us to believe. He could have stabbed the couple without gloves and then donned a pair to write on the car door, but this seems rather unnecessary when he simply needed not to touch the door with either his fingers or palm. And again, if he possessed gloves that day, why logically would any fingerprints found on the car door be his?
 
In terms of the handwriting, our next task is to sit at a table with pen and paper at hand, and write the wording from the car door. We then need to follow this up, by squatting in front of a wall with some paper pinned to it and write the same wording without resting your palm on the wall and note the results. One would expect a discrepancy, let alone all the contributing factors that faced the Zodiac Killer at Lake Berryessa on September 27th 1969. The final option, suggested by some, is that the killer wrote on the car door before attacking the couple. This would circumvent the blood issue, but would have relied heavily upon his method of operation going exactly as planned, otherwise the only smear on the car door may have been in black ink.
 
To view a comprehensive discussion on this topic and pursue other lines of reasoning, please visit the following thread at the ZodiacKillerSite Forum. Or click the banner below, to join or access the main index page.      
http://www.zodiackillersite.com/viewtopic.php?f=29&t=806

Kim Rossmo is a Canadian criminologist who examined the Zodiac crimes in depth, giving a detailed account of the killer's possible movements after each crime and a likely location to the most notorious murderer in US history, employing the art of geographic profiling. It is an extremely interesting and thought provoking analysis, using the logic of the human mind, that involves 'the least effort principle', 'comfort' and 'buffer zones', along with a fair sprinkling of common sense, to reach inside the mind of the Zodiac Killer and examine why he did, what he did, during his brief but nonetheless devastating ten month reign, that struck fear into the heart of Northern California and beyond. See Zodiac-Killer-geographic-profile-by-Kim-Rossmo-Ph-D.
In two previous articles 'The Lost 20 Minutes' and 'East to Benicia', two different base locations have been identified as the possible residency of the long sought after Zodiac Killer, but this time we will predominantly be examining his logical exit routes away from each of the murder sites using the premise that the Zodiac Killer would immediately head for a secure or safe location after each crime, usually home, to destroy or dispose of any incriminating evidence transferred during the commission of his evil acts. This article will back up the 'East to Benicia' article, in so far that his likely residence may possibly be in the Benicia area or slightly further south, in the region of Martinez CA or Concord CA.
The Zodiac Killer's movements directly following the shooting of David Faraday and Betty Lou Jensen on Lake Herman Road appeared the most telling, The Zodiac Killer was estimated to have left the gravel turnout at 11.15 pm, the same time Stella Borges left her ranch. If the Zodiac Killer had turned west to Vallejo he would have passed Stella Borges, however she reported passing no vehicles, lending weight to the hypothesis the Zodiac Killer headed east in the direction of Benicia or beyond.  

It would then be just a short journey over the Benicia-Martinez Bridge; (officially known as the George Miller Memorial Bridge), to the immediate towns beyond the Carquinez Strait.
The Zodiac Killer also appeared, on the face of it, more familiar with the Lake Herman Road and Presidio Heights areas, as opposed to Blue Rock Springs Park and Lake Berryessa regions, as he reveals in his correspondence with authorities. In the San Francisco Chronicle letter mailed on July 31st 1969 he refers directly to Lake Herman Road, even pointing out that Betty Lou Jensen's feet were facing west, which indeed was correct. In the 'Debut of Zodiac Letter' mailed on August 4th 1969 he recalls 'Last Christmass In that epasode the police were wondering how I could shoot + hit my victims in the dark. They did not openly state this, but implied this by saying it was a well lit night + I could see silowets on the horizon. Bullshit that area is surounded by high hills + trees'.
His final confirmed murder, that of Paul Stine on October 11th 1969, portrayed the picture of a man confident in these surroundings. Committing the crime in a built up area, close to 10.00 pm at night and escaping from the scene, showed distinct elements of pre-planning and a knowledge of the area. However in both of the Zodiac Killer's phone calls to police after Blue Rock Springs Park attack and Lake Berryessa, his directions were questioned on both occasions. He fails to mention Blue Rock Springs at all, only Columbus Parkway, stating 'I wish to report a double murder. If you will go one mile east on Columbus Parkway to a public park, you will find the kids in a brown car. They have been shot by a 9 mm Luger. I also killed those kids last year.... Good-bye'. In his Chronicle letter he only refers to Blue Rock Springs as 'near the golf course in Vallejo'. If it were the case that his knowledge of Lake Herman Road and Presidio Heights were greater, then his two southernmost crimes were possibly the areas he frequented the most, although all are punctuated by lakes or expanses of water. Indeed, Blue Rock Springs is only four miles from Lake Herman, the greatest distance any major body of water lies from any of the crime scenes. If the Zodiac Killer resided in Benicia, Martinez, Concord, Lafayette or somewhere around the vicinity of Walnut Creek, then his knowledge of Lake Herman Road would logically be greater. This may suggest ease of access both to the Benicia and Vallejo areas, as well as to San Francisco via the Oakland Bay Bridge, where he may likely have worked or at the very least traveled to mail the majority of the Zodiac letters. It is only a 37 mile journey from Martinez to Presidio Heights and only 27 miles from Walnut Creek..

However there was unaccounted time from the commission of his crime at Blue Rock Springs, to the placing of his first phone call to police dispatcher Nancy Slover of approximately 40 minutes. The short journey to the phone booth at Springs and Tuolumne was approximately 10 minutes journey time, therefore it has justifiably been theorized that the Zodiac Killer used this time to go home first, stash his weapon, remove any incriminating evidence, before readying himself and venturing back out to place the phone call, placing himself under far less risk of detection than being exposed in a public area carrying the smoking gun.
If this chain of events were the likely scenario, and the Zodiac Killer lived in the southern regions of Benicia or Martinez, then the maximum window of 40 minutes would exist to travel home and return to the payphone.   

The journey time from Blue Rock Springs to Martinez is roughly 18 minutes and the return journey to the payphone is 17 minutes, with a 5 minute turnaround, making this southernmost destination the furthest possible round trip to account for the 12.40 am call.
Although this gives us a further problem. Are we to believe the Zodiac Killer, after murdering Darlene Ferrin and seriously injuring Michael Mageau would traverse the Vallejo and Benicia areas, over the Carquinez Strait to home and then return all the way back to the payphone at Springs Road and Tuolumne. It appears to make the 'least effort principle' look like hard work, and criminals are like the rest of us, in some aspects at least, that the easier option is the preferred choice. Despite the fact the Zodiac Killer seemed determined to place the phone call, obviously the least time he was in the public spotlight, not only carrying a murder weapon for one part of the journey, but heading back to an exposed intersection, the better.
The thought of the Zodiac Killer heading towards the Benicia area and beyond, reaching the safety of home, then making the choice to place himself back into the firing line and return to the close proximity of the crime for a second time, would make even a madman look irrational. As explained in the 'East to Benicia' article, a further option exists.  
If he lived in Benicia or somewhere in that region, as his movements suggested after the Lake Herman Road double murder, then knowing the phone call would place him at greater risk, it is conceivable to believe he discarded the weapon before making the phone call to Nancy Slover, but not at home, in his mind reducing the risk of being stopped carrying the 'smoking gun'. So the next thing to do is examine his possible movements during this timeframe.
He was familiar with Lake Herman Road, and in near isolation, dark and free from prying eyes, it would have been a perfect disposal site for his weapon, particularly bearing in mind Lake Herman was situated near to his first murders. A round trip from Blue Rock Springs to Lake Herman, with time spent to exit his vehicle, possibly remove his gloves, change clothes, wipe down the weapon and toss the evidence into Lake Herman, before returning to the payphone at Springs Road and Tuolumne, in total 10 miles, would have taken approximately 30 minutes, obviously dependent on time spent at the lake, however nearer the time of 12.40 am, the time the call was logged. Any stop by police now would have held far less risk.

Paul Stine was brutally murdered in his taxicab during the evening of October 11th 1969 at the intersection of Washington and Maple Street. The Zodiac Killer's last known movements were north up Cherry Street and towards the Presidio. 
After killing Paul Stine the logical approach, considering he may well have been covered in blood, would have been to return to his waiting vehicle and get the hell out of San Francisco as quickly as possible. So presuming his apparent knowledge of the obscure Lake Herman Road and his movements towards Benicia after the double slaying of David Faraday and Betty Lou Jensen, what was his likely exit route away from San Francisco.
After the murder police vehicles would have converged towards the Presidio Heights area from the southerly, westerly and easterly directions, so the least time he spent in San Francisco from a safety aspect, would have been the most preferable option. If his vehicle was located somewhere near the Jackson and Maple Street intersection, then the obvious choice would have been to remove himself from any contact with approaching vehicles, by accessing West Pacific Avenue, creating this buffer zone between him and the police. His next logical step to depart the San Francisco area in the fastest time possible, would have been the Golden Gate Bridge, past the Sausalito area, towards and across the Richmond-San Rafael Bridge and the 20 mile journey back from Richmond to Martinez.  
Another interesting aspect of the Martinez and Concord areas is concerning the Modesto Abduction of Kathleen Johns on March 22nd 1970, if you believe this to be a Zodiac crime. After she entered the assailant's vehicle, he drove her around through the the countryside of Tracy, CA before she made her escape across a field. The route from Modesto to Tracy and on to Martinez, Benicia and Vallejo is virtually a direct route as the crow flies.  

The route also passes by Mount Diablo, a location that featured prominently in the Button Letter he mailed to the San Francisco Chronicle on June 26th 1970, as well as the Little List Letter on July 26th 1970. The suggestion here is that after abducting Kathleen Johns he was unlikely to head away from home, but again travel toward safety, yet create the necessary buffer zone between the crime location and his residence. On this occasion Tracy CA would provide a 57 mile buffer zone to Martinez.
Finally and probably the most controversial crime attributed to the Zodiac Killer, was the costume driven attack on Bryan Hartnell and Cecelia Shepard on September 27th 1969. This would be the furthest the Zodiac Killer would ever travel in search of a victim.
His phone call to police dispatcher Dave Slaight, again appeared to show little in depth knowledge of the area, although in all likelihood he had probably visited the area at least a few times from a recreation standpoint, possibly fishing being one of his pursuits, when he wasn't out murdering people. After brutally stabbing both victims he made his second phone call from 1231 Main Street in downtown Napa, stating "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" and after a brief pause uttered the words  "I'm the one that did it".  However the location of the attack is only 0.7 miles north of Park Headquarters. The simplest route back from Napa is California State Route 29, past American Canyon, directly through to the bay area, north of the Carquinez Strait. This would provide easy access to and from the Lake Berryessa region. 
Placed altogether, the movements of the Zodiac Killer after the Lake Herman Road murders, his direction of travel in the Modesto Abduction, as well as the direction taken from Lake Berryesssa to Napa, including the 'buffer zone'  phone call at the mid point, before continuing on to the Benicia region or beyond, and his logical exit route from Presidio Heights, centers the focus squarely in the region either side of the Carquinez Bridge. But who said murderers make sense.