I want to go back to the basics of my inquiry into origins of Alexandrian Christianity (which I happen to think is the beginning of Christianity as such).
Let's begin with the most basic physical 'fact' about Christianity in Egypt as summed up in the second preface to Severus Al'Ashmunein's History of the Coptic Patriarchs:
And the Virgin Mary bore him in her womb and brought him forth, by a mystery to which the intelligence of creatures cannot attain, and by which he exalted her above above all other created beings in heaven or on earth; above the Angels, the Powers, the Principalities, the Cherubim and the Seraphim, and all whom God has made in heaven or on earth. For she became the throne of him who is Lord of the first and the last, without division or change, of him whom no space can enclose, and no time contain.
And when, in his unattainable wisdom, established his dispensation, and the Union of his Humanity with his Divinity, the mystery of which is hidden from all in heaven or on earth, he chose his disciples, the apostles, and gave them the great commission, authorising them to bind and to loose. And so likewise their successors after them inherit this gift in all regions of the world, each one following his predecessor. Thus the inheritance of this power, which Christ gave to the great father and evangelist, Mark, the apostle, is carried on to his successor, the patriarch who sits upon his episcopal throne in the great city of Alexandria, in the midst of the regions where he preached.
Saint Mark, then, was the first patriarch who fed the flock of Christ; and in after times he was followed by the inspired fathers and patriarchs, generation after generation. This see of his is independent, and separate from all other sees.
Now I know that there are some who say that the whole idea of Alexandria being the original 'See of St. Mark' is complete nonsense. Yet I am not so sure. I have long been an advocate for the idea that Christianity - and the gospel in particular - was first established in Alexandria. If the story of Mark coming to Alexandria is our only - albeit legendary - detail about how Christianity came to the city, on some level we just have to figure out some way to make sense of the tradition.
Indeed Christianity has to be thought to have been founded SOMEWHERE. Do the various legends about St Peter coming to Rome have any more sense? Or what about the legends associated with Antioch that make their way to Acts? In this case the idea that Peter and Paul's miraculous reconciliation forming the foundation of the Catholic Church is flatly rejected by the text of the letter to the Galatians.
I also DESPISE the Protestant influence over the study of the early Church. It is because of them that we even CONSIDER the idea that the religion could have just developed 'naturally' (which means without a central ecclesiastic authority).
Now just to keep things in perspective. The Catholic Church and various other churches all reinforce that there was a firm ecclesiastical body FROM THE VERY BEGINNING establishing and assuring a firm orthodoxy established by those who claimed to be eyewitnesses of Jesus.
I happen to buy into this scenario which gets me in trouble with people on both sides of the academic spectrum.
On the one hand there are the atheists who say 'you can't believe that there really was a historical Jesus.' To them I say, the Alexandrian tradition ALWAYS emphasized the divine nature of Jesus. Can I really deny that someone like Mark claimed to have an encounter with the angel of the presence or witnessed God the Father THROUGH him? How can someone deny that a claim like that was made in antiquity? Only a bigot could only seek to disprove something without trying to understand it.
On the other hand almost all of the most knowledgeable people in the field of the early Church Fathers came into contact with Christianity through a familiar set of EUROPEAN assumptions about the Church. To argue that ONLY the legendary details associated with St. Mark's visit to Africa is about as crazy as crazy can be.
However the bottom line for is that I think the gospel was first written in Alexandria. Clement of Alexandria incorporates the legendary details of St. Mark's visit to Alexandria with the idea that the Alexandrian Church preserved that gospel and protected it WITH A SPECIFIC GEOGRAPHICAL REFERENCE - i.e. 'the Church of St. Mark.'
Most people who study the Mar Saba document never give the reference to 'the church of Alexandria' even a second thought. They don't spend much time reflecting on the description which follows:
Mark came over to Alexandria, bringing both his own notes and those of Peter, from which he transferred to his former book the things suitable to whatever makes for progress toward knowledge. Thus he composed a more spiritual Gospel for the use of those who were being perfected ... [and] to the stories already written he added yet others and, moreover, brought in certain sayings of which he knew the interpretation would, as a mystagogue, lead the hearers into the innermost sanctuary of that truth hidden by seven veils. Thus, in sum, he prepared matters, neither grudgingly nor incautiously, in my opinion, and, dying, he left his composition to the church in Alexandria, where it even yet is most carefully guarded, being read only to those who are being initiated into the great mysteries.
But since the foul demons are always devising destruction for the race of men, Carpocrates, instructed by them and using deceitful arts, so enslaved a certain presbyter of the church in Alexandria that he got from him a copy of the secret Gospel ...
There is a very good reason why Clement speaks of 'THE CHURCH of Alexandria' for it is well known to historians of Coptic Christianity that the first church of that tradition was the so-called Martyrium of St. Mark. Birger Pearson has written about this place. Many others too. Yet only Harry Tzalas has identified where this building was located. It is here.
Harry Tzalas comments on the satellite photograph as follows. You can see east of Cape Lochias and and not far of the Bibliotheca Alexandrina [the circular building], the Chatby Casino. As you asked how near it is to the Coptic Church crypt…. just move slowly South, the large white building in the shape of a Basilica is the St. Mark College and in front of it, on the Corniche side there is the Hellenistic Necropolis.
Moving further south, crossing the tramway line you have a large gray void of buildings, this is the area of the Christian Cemeteries and the Copt expends towards the perpendicular avenue. It is a photo of 2002 so the new large church was not yet built.
You will note a superimposed dotted semi-circular formation and North another rectangular formation. I was puzzled by this semicircle, which in the shallows [goes up to only 3 m depth] looks like a deep carving reaching a height of circa 90 cm above the sand bottom. The diameter is of circa 500m, too large for any structure foundations! As it touches the Chatby Casino I had to find an answer.
Finally from old maps I noted that one of the 7 canals that went in Mediaeval times in the sea was reaching this exact site. The analysis of the sediments on this circular formation, made by the Department of Marine Geology of the Patras University confirmed that the incrustation was due to the contact of the fresh water and the sea water. So the Martyrium of St Mark was neighboring running water, which would have given vegetation thus accounting perhaps the name of “Boukolia”, “Boulolou” etc.
As to the rectangular formation I still have no answer, but it looks as natural and not man-made. We did, west of the semi-circular formation and nearly in front of the Casino trace in the shallows a large and smaller Proto-Christian capitals.
