Okay. Good evening, everybody.
This is fabulous. So today's lesson is ...
No what I actually wanted to say was just welcome to this fabulous place in Harris Manchester College.
And many thanks to the college for having us here.
I'm Damian Robinson, I'm Professor of Maritime Archaeology here in Oxford, and I'm the Director of the Oxford Centre for Maritime Archaeology.
I've also worked with tonight's speaker Franck Goddio for a considerable time now.
And I'm delighted that he's here with us tonight to officially begin our conference:
Alexandria and the Sea II.
Alexandria and the Sea I was unfortunately cancelled due to Covid.
But thanks to the encouragements and the support from our funders at the Hilti Foundation,
particularly Christine Rhomberg, who nudged us both to get back on with this,
we're here today in person
and so it's great that everybody could travel both from Oxford, but also from much wider to be with us.
So thank you very much for coming here. And the second reason that I'm delighted that Franck is with us today is to
celebrate the publication of his latest book on the Iseum of Antirhodos Island.
So this started off as a paper in the online version of Alexandria in the Sea, and then just kind of grew into a book from that.
And I think what it shows is the value of long term scientific research in the Portus Magnus.
Franck and his team in the European Institute for Underwater Archaeology,
where they've been working since 1992, carefully mapping, excavating, studying the finds and now publishing
this fascinating archaeological site. So for me, it's a privilege to work as part of this vibrant team.
Tonight, Franck is going to introduce us to another temple, not the Iseum, but the Poseidium, and to situate it within the port and the city.
So, I can probably feel another book coming on from this. But over to you Franck.
Franck Goddio: Thank you, Damian, for the nice words,
and thank you to everybody for your presence.
Tonight, I would like to make a presentation of one of the few temples which could have been located in Alexandria.
Very few temples to date
were located in Alexandria's ancient city.
We know about the presence of a temple to Poseidon thanks to Strabo.
Strabo, in his description of the Portus Magnus said: "The Poseidium, an elbow as it were,
projecting from the Emporium, as it called, and containing the temple to Poseidon."
I have always been surprised by this sentence.
Why is Strabo calling this peninsula Poseidium?
He could have said the temple of Poseidon is on a peninsula, but he names the peninsula as the Poseidium.
Thus, he must have had some information about what was this Peninsula.
And as a matter of fact, doing the survey and the underwater excavation on the Poseidium,
we were able to discover that that peninsula was much more than bearing a temple and a sanctuary to Poseidon, as you will see further.
We have the east port of Alexandria, which covers as per today, 668 hectares, which is a huge area.
And on that area, we have, since 1992, performed a lot of electronic surveys and underwater excavations.
You can see here on that map a multibeam bathymetric coverage, meaning the relief of the bottom of the sea.
And you can see the kind of a shadow of what was
the Portus Magnus in the antiquity.
After 20 years of work, we are now able to present a precise map of the contours of the Portus Magnus, as it were, during the Ptolemaic time.
And we have a version of the Portus Magnus in the Roman time, which changed a little bit.
You have here the Portus Magnus as it was during the Ptolemaic time,
at the end of Ptolemaic time.
The Portus Magnus has been divided by Strabo in two main elements. East of it what he calls the Royal Quarters and west of it,
the Navalia, the shipyard and trade dock.
We will focus our interest on the Royal Quarters.
In the Royal Quarters we have now defined the contour of the sunken land, but also identified several important monuments.
And of course, you can see here on that map that there is only one peninsula,
the one described by Strabo, which is in the middle of the Royal Quarters.
You can see that peninsula on a multibeam bathymetric map here.
And this peninsula, as you can see, is located between the military ports, which are in the north and a central port,
which is the emporium port, which has a perfect shape as Kibotos, box.
But it was not the Kibotos, which was built on the west port of Alexandria.
That Peninsula is named the Poseidium.
The underwater excavations will indeed reveal that far from bearing only a temple to this god, Poseidon,
it was a whole sacred complex, proceeding from a grandiose urban concept which had been created
to the glory of this god of primodial importance for Alexandria, of course.
Let us zoom on the base of that Poseidium, that peninsula here.
We have here a detailed bathymetric map, multibeam, of the base of this Peninsula.
North, you have the military port with some moles and quays, and south the Emporium port.
And the base of that peninsula covered 3.5 hectares, which is quite a huge area.
You can see, let us post on that map
all the red granite columns that have been identified during our survey.
And sometimes excavation, of course, is not representing all of the red granite columns,
but you can see the several hundred fragments of red granite columns spotted in that area.
With my pointer
you can see here a long line
in another colour, which is a line of wooden posts.
Thus, we can say that the whole base of that Poseidium has been reinforced by wooden posts as we will see.
Let us zoom now to the north part of that base.
There we were able
to find and excavate, by spot excavation
not totally excavated, of course, a 250 m long colonnaded street.
And the columns on each part of the huge alley,
that colonnaded street, are red granite columns with moldings at their two extremities.
And their diameter is 70 to 60 cm each of them.
But what is very interesting is that
the base of that colonnaded street is formed by a cofferdam
made of wooden posts and planking
retaining a basement [foundation] made of mortar with limestone embedded in the mortar.
This was done, of course, to have the very solid ground to support all of those red granite columns.
And what is very impressive is that this pattern is found all alongside that colonnaded street.
And that colonnaded street you can see here about 250 m of it, but it goes towards what is now the Corniche of Alexandria.
And it links exactly a spot which is now the centre of the Bibliotheca Alexandrina, to the Poseidium.
It's very fascinating. You can see here a representation of the wooden posts here,
and of the planking in between the wooden posts and the mortar with limestone embedded into it.
It's a 300 m cofferdam, beautifully built.
Here you can see samples of these red granite columns with the two moldings at their extremity here.
And we have some of them also of 50 cm diameters, in some spots.
So they were not all of the same diameter and length.
Of course, we have performed wood identification and a lot of carbon 14 analysis on this wooden posts and planks.
Most of the posts are from Ulmus, imported wood, and the dating seems quite early in the Ptolemaic time.
Same for the planks, Ulmus, which have dating,
perfectly coherent, very early in the Ptolemaic time.
Thus, this base of this colonnaded street has been created early in the Ptolemaic time.
Now, let us go towards the south west.
That long colonnaded street is leading to a vast square, an agora, a beautifully paved square.
And here also we have a very peculiar foundation pattern. Around the square is exactly the same foundation made with cofferdam
and mortar with limestone embedded into it. In the middle of this agora, are only wooden posts but not mortar. And to the periphery of that agora
you have, of course, to consider that the red granite columns, which are represented by pink spots,
have fallen and are not in their exact position, original position.
But you can see that this agora was surrounded with colonnaded columns.
A very interesting thing also we can say about the pavement.
Inserted among the pavement we found
ancient anchors. We have excavated 15 % of that agora, and on the 15 % area we found 45 of those ancient anchors.
Thus the relation with Poseidon is here
quite interesting. Ancient anchors were used among the pavement
to make the flooring of that
vast Agora here.
We have done also analysis on the wood which was in the middle of that agora and reinforced with
wooden posts and planking, the ground of the Agora, but not on the periphery.
At the periphery, we had exactly the same patterns than the colonnaded street and in the middle,
the wooden posts, most of them were from cedar, Cedrus libani, an imported and a very expensive wood at the time, and as the planking was of pine.
And the dating fits exactly with the dating of the foundation of the colonnaded street:
very early Ptolemaic time.
Thus, we are here in presence of an infrastructure which has been conceived at the beginning of Ptolemaic time, third or early second century BC.
Seeing from afar, you have this colonnaded street leading to the agora,
but you can see here that south of the agora you have evidence of very important archaeological remains.
And we will zoom into that square now. You have here the bathymetry of that area which you give a 10 cm accuracy.
But in order to have a better view of it, we have done a generous stereo-photogrammetry of the whole area, 70 by 50 m, which represent,
I think, about 18,000 pictures taken by Christoph Gerigk, which were assembled, and we have a very clear vision of that area.
You can see there
quite well organised vestiges, inside that rectangle here.
And we have performed excavation.
And we discovered that it is the remains of a very important monument.
The centre of that monument is founded on a mortar base.
Very important mortar base, 1.5 m thick.
All around that mortar base you have the remains of the limestone blocks of the monument.
And south and southwest of it,
you have all alongside that monument fragments of the columns,
which were proceeding from that monument, and which collapsed towards the south-southwest.
Interesting also if you can follow my pointer,
we were here, of course, under this mortar block we cannot excavate because it's a huge mortar block that we have no access under.
But here as the mortar has been totally dismantled during an earthquake, obviously, we could find wooden posts.
Which were reinforcing the ground, most probably everywhere under that mortar.
We could prove it here with several rows of posts and a little bit here and there with the remains of some wooden posts, if you follow my pointer.
And we have a very impressive amount of red granite columns proceeding from the temple.
Yes, the presence of this mortar foundation
with limestone embedded into it
is consistent with the construction practices,
particularly in region with unfavourable
of course, or unstable soil conditions, which is attested here, of course, by the presence of wooden posts and planking
which are reinforcing the ground.
The hydraulic mortar was perfectly well adapted, of course, given the proximity of the sea and also the high ground water level.
We were able, with the excavation, to draw a layout of that monument, which is developed between here and nearly 50 m long.
And from the stereo-photogrammetry,
if you follow my pointer, you can see here the evidence of a large square, which is covered with a mortar,
and assuming of it you have a very well organised remain of limestone ashlars, which are the remains, of course, of the crepidoma.
Now, we were able to register, to list, all the fragments of the red granite columns, and we were surprised, because those columns are from different diameters.
The great number of columns
have diameter 85 to 80 cm.
We have also fragments of 75 to 70 cm.
Fragment to 65 to 60 cm.
And we go even down to 55 to 50 cm,
35 to 30 cm. The ashlars are all the same:
1.20m x 50 x 50 cm. Very well calibrated,
beautifully preserved. In another place of the Portus Magnus, at the tip of the Royal Island of Antirhodos
we had the chance to discover intact columns.
Intact red granite columns similar to those here.
But the length of that column is 5.6 m and its diameter ranged from 83 to 80 cm,
and the ratio length, diameter length, gives us a ratio of seven.
Thus, a column of 80 cm had about 5.6 m length.
Well, and of course, a column of 60 to 65 cm were 4.2 to 4.5 m long.
Of course, this is a hypothesis, but taking into account that the columns are all alongside that temple,
we can assess with certainty that it was a peripteral temple,
meaning a temple surrounded with columns, you did not have only the columns only at this facade but all around this temple.
And those columns must be, of course, the biggest ones, which fit perfectly,
the columns of 85 to 80 cm diameter with a length of about 6 m, more or less.
Then, where could we put in this case, distribute the columns?
First, taking into account the diameter of the columns, 85 to 80 cm, the biggest ones,
and taking into account a reasonable intercolumniation distance between the axis of two columns,
most probably this temple had eight columns on each facade. Thus, it was most probably an Octostyle Peripteral temple
surrounded by the columns. The 75 to 70 cm columns, in this case, must have been on each part of the temple, first on the Pronaos,
if you followed my pointer,
and it does correspond nicely with the place where we found them around here, and here
on what could have been the Opisthodomos.
Though we are not sure whether the Pronaos was towards the southeast or towards the northwest,
because, of course, during excavation, we were not able to have that type of a precision.
But we will see that we can draw some hypothesis after.
Where to put the columns of 65 to 60 cm diameter? Most probably in the cella.
And this would have given, more or less, because fragments are of course missing,
which has been recuperated and most probably there were intact columns which had been recuperated during centuries.
Most probably we had there six columns in a row, meaning 12 columns in the cella of 65 cm diameter.
These are hypotheses, but also most probable hypothesis, taking into account what is left on the ground.
And the dimension of the basis of the temple, the Crepidoma, was of 43.5 m to 18.5 m,
which is quite a sizeable temple, and the sanctuary by itself was 35.5 by 11 m there.
Another interesting feature is that towards the southwest you have several mortar blocks, or a very big mortar block,
which has been destroyed during an earthquake in the axis of the sanctuary.
And of course, one of the hypotheses could be that this was the main altar for the temple, of course, the altars of Greek temples
were outside, as in the temple here. It would fit quite nicely.
And in this case, the temple would have been open towards the south east.
Which means, towards the city. The direction of the temple is exactly
southeast northwest on the southeast - northwest axis.
The question, of course, is the identity of the temple. Very few artefacts
have been found of the temple, but we are on the peninsula, and it's the only important monument spotted in that peninsula.
Thus, we can say with near certainty that we are in the presence of the temple of Poseidon, which was a very important sanctuary.
Now, the question arises whether this temple was opened towards the northwest or the southeast.
Of course, the presence of those mortar blocks towards the southeast could lead us to say,
okay, it's open towards the southeast, but you will see further,
that other elements could challenge this conclusion.
We made, of course, wood analysis and carbon 14 analysis on the wooden posts
and here we were surprised. We are no longer in the early Ptolemaic time, but we are early Roman time.
Thus, when Strabo came to Alexandria it was between 26 and 20 BC,
according to the prefect, which was in Alexandria in Egypt at that time.
And of course, when he's talking about the temple to Poseidon, he is describing a Ptolemaic temple.
Thus, most probably, we have here something which has been rebuilt during Roman times.
The artefacts are more or less confirming the dating.
We have very few ceramics from the beginning of the first century AD.
Very few artefacts, some semi-precious red stone, a little bit of jewellery,
a nice ring which was left and escaped to the looting and quite a lot of tokens, lead tokens, which were of no interest for the looters.
And as everywhere in all sanctuaries that we are excavating, whether in Aboukir Bay in Thonis-Heracleion,
Canopus or in Alexandria, everywhere, small bits of gold, very strange, jewellery scattered everywhere.
Now we have also the question where ...
First, the temple we are in the presence of today
of the remains of the temple,
are, obviously, not the temple Strabo was describing, but most probably we could
suggest that a temple which has been destroyed,
or which was too old at the time of early Imperial period, has been rebuilt on the same site, more or less in the middle of the fourth century BC environment.
We have here the temple, and in white
you have the axis of the temple towards the northwest.
Let us see now what is towards the northwest in that area here. Just here.
Here the multibeam bathymetry show you that there are some interesting remains.
And we performed several excavations on that area.
We found out that it is a vast rectangle surrounded with very nice limestone ashlars exactly of the same dimensions
than the ones of the temple 1.20 m by 50 cm by 50 cm.
But we can think maybe that was a monument there.
But we were surprised when we excavated.
There was no remain whatsoever except a vast rectangle filled with sand.
Only if you follow. But we see after.
And first we took away the sand.
And after 1 to 1.2 m of sterile sand, there is a 40 cm thick layer of calcareous deposits in the nodular concretions,
and thick crusts forming massive layers of carbonate incrustations of tubular fabric from freshwater animals.
Thus, during centuries, most probably
this rectangle, surrounded by a very nicely built wall, was filled with fresh water.
Because all those concretions correspond to formation in a freshwater environment.
We can say and assert that we are in the presence of a lake, a lake nearly 2 m deep here,
1.8 m deep, etc, because under the concretions, you find the bedrock.
Nothing else., flat bedrock.
Thus seen from afar, you have
the colonnaded street, the agora, and here the temple, and just in the axis
of the temple, of exactly the same dimension of the crepidoma of the temple,
was the lake.
Now in that lake, northwest of it, there is a very large, thick broken block, 6 by 6 m and 1.5 m high.
It's huge. It has been broken during an earthquake, only an earthquake can break such a thing.
And it does correspond to a massive base or basement [foundation].
And it's exactly centred on the axis of the temple and of the lake.
And in the middle of the lake here we have, but much smaller,
Some collapse mortar blocks. And we have done excavations
in the lake, where we have discovered here three fragments of a marble colossal statue.
And here, an element of an obelisk.
This fragment of an obelisk, most probably proceeding from Heliopolis,
dates back from Sethi the 1st and very interesting enough we see another fragment of that obelisk
have been found much further towards the shore at,
the northwest, at that site can see here the fragment of the obelisk and one of the colossal fragments of a statue,
which was absolutely so eroded that it's absolutely unidentified.
Here it looks like an elbow or something, but very difficult to identify.
But there is something very interesting. We are here in the middle of the peninsula.
That peninsula when the temple has been destroyed,
most probably in the 4th century A.D., because nothing on that peninsula is more recent than
the end of 4th century A.D. We have here an earthquake in 365, which could correspond very well to the destruction of that monument.
But what is interesting is that that peninsula, have obviously been above water for
quite a lot of centuries.
Most probably it a sunk in the 8th century, but it was totally abandoned.
In some place we found Byzantine gold coins,
but it was at the extremity of it.
Thus, if we are not on the seashore,
most probably, the remains of those monuments, the colossal statue and the obelisk, were not far from their original place.
Whereas, on the western part of the coastline of the eastern port of Alexandria.
other remains of the same order, meaning fragments of fasciculated columns, obelisks,
sphinxes, architraves, lintels, have been discovered.
But they were alongside the sea shore and they were all coming from
ancient destroyed sanctuaries. And they were thrown there to protect from marine erosion,
the monuments which were built along the coast at a much later period.
But here we are not on the seashore thus there is not a single reason why an element of an obelisk and other
red granite fragments that we found, would have been thrown in the middle of port.
Thus, we can say that most probably the obelisk here was not far from its original place.
If we see the map, you have the lake, the basement,
the basement here, the colossal statue here and the obelisk there.
It's of course tempting to say that the original obelisk was exactly on that basement.
because you correspond very well to the falling direction for all the columns and all the ashlars of the temple.
But it's an assumption of course. But seen from afar
we have a very interesting fact:
You can see here, if you follow my pointer, the temple.
the lake, the basement. Exactly on the same axis.
But look north of that. The axis of the colonnaded street
crosses, exactly the two axes
at the basement point. Thus, it cannot be a random thing.
It has to be... It was done in purpose, of course, because you have a 300m
colonnaded street, leading to an agora and in the axis of the colonnaded street, a very big base which would have supported... what? It could be an altar?
It could be a colossal statue? It could be an obelisk?
This is up to our imagination, of course,
but there was something very big here which could have been seen from more than 300 m away.
This 3D would
show you how those
arrangements of monuments and colonnaded street
were done with the temple, the peripteral octostyle temple
the lake, the big base, and this colonnaded street, the agora.
Here there is no assumption, there are just facts.
After this, we can have some assumption that here, except for, of course,
the pattern of the temple, which was most probably looking like this one.
There are just archaeological facts. Let us go further.
Let us follow the same axis because it looks interesting to follow that axis here.
Let us go northwest where you see the round red circle here.
What is there? Very interesting thing!
We have archaeological remains here, but it's not organized.
It's very... it has been heavily looted and very perturbated.
But there are columns of 30 cm of diameter, which are... it's not big, it corresponds to a column of 2.2, 2.5m high.
Thus we are on the small, with a small column capital fitting with them and all around we found interesting remains
also. You will see. We found in the ground,
under the pavement, some bronze statuettes,
or elements, broken elements of bronze statuettes,
everywhere. The ceramic…
it's extremely poor in ceramics. Thus, the ceramics we found were really at the bottom layer.
Thus, it doesn't date at all, dates at all
that sanctuary when it has been destroyed
because the upper level has been totally eroded by the waves and the swell and what remains is only the heavy elements which were in the ground
which has disappeared. I forgot to say that more or less 3 m of ground have been disappearing from the erosion.
And, on the lower level, we are finding ceramics from
the very early Ptolemaic time, end of 4th century, very beginning of 3rd century here.
Small elements and bits of broken bronze statuettes, head of a priest.
Very impressive. It's a beautiful head of a priest and sphinxes.
Two sphinxes of quartzite.
Again, a small bronze statuette that most probably, this could be, very well, Poseidon. And at the same scale,
a finger, bronze finger from a colossal statue.
Very impressive, colossal statue. Thus, we are,
here, most probably on a small temple devoted to Poseidon.
What is interesting to see is the position of that temple here, which is very close to the quay of the military port,
and those small statuettes were, are not of exquisite qualities,
they are nice, but must have been presents and donations to that small sanctuary here.
But again, you can see that on a line, you have the temple to Poseidon,
the lake, the base and another small temple.
Thus, we have here a 3D representation.
Of course, the small temple, we just can... it's represented here as... only,
to show that there was a temple there, but we don't know it's shape
we know only that the columns were 30 cm in diameter,
red granite columns. But you can see, it's a whole
ensemble of monuments which were on the base of that Poseidium.
And of course, we have now, if you see from far, how to reintegrate the obelisk and the colossal statue.
We are here in an hypothesis and imagination, of course, but we could think of an obelisk here,
which this disposition has a very strong Roman flavor.
Because, of course, during the Egyptian time an obelisk would not have been used as a focal point like that.
Okay, if there were one obelisk only, most probably that obelisk was on the main base,
that we found, and which is here, because there are two bases that we have here.
But could it be also an altar? It could be, in this case, the temple will be open towards the lake and the altar.
And it will be a very interesting set. If we go back...
here we have: a small temple, an altar, a lake with most probably a colossal statue of Poseidon, of course, and the temple of Poseidon.
Thus, the question remains whether this temple is turned towards the northwest or towards the southeast?
Towards the southeast, it's interesting because most of the Poseidon temples are oriented towards the southeast, that it's in Greece and the
temples were always oriented toward a maritime horizon, which here the maritime horizon is towards the northeast, not the towards the southeast.
Thus the question remains, if we have this obelisk here, we could dream, of course, of a colossal statue of Poseidon there.
But these are mere suppositions.
But let us go further because that axis seems quite interesting.
Why don't we go along side that axis and let us go much further towards the axis of the temple and of the lake?
Here. It just hit a spot where, this is of course to be challenged and there has been quite a challenge,
on the spot where the lighthouse could have been.
In any case, that temple was oriented,
the axis of that temple was going towards the entrance of the Portus Magnus, which makes sense.
Here you have the maritime horizon for this temple to Poseidon.
But, if ever the lighthouse
was there with a statue of the saviour
god on it, you will have the temple, the lake,
a monument under the temple and the maritime horizon would have been the most famous maritime horizon of that time:
the lighthouse of Alexandria.
Thus, I think it's worth to think
and to see what could have been the Arrangement
of this peninsula and this could explain why Strabo is talking about, not about the peninsula
an elbow of land, the Poseidium,
which bears the temple of Poseidon but not only the temple of Poseidon,
it was a whole grandiose
urban arrangement with the colonnaded street, the agora paved with limestone
anchors, the temple to Poseidon, the lake,
most probably a colossal statue of Poseidon,
another monument, a small temple and 1.5 km after,
exactly, very precisely,
to 0.5 of a degree, maybe the lighthouse.
Thus, I can say that the base of the peninsula of the Poseidium.
was developed as a vast sacred area dedicated to the saviour god, Poseidon
in a grandiose architectural and urban
planning concept
with more than 300 m colonnaded street,
the agora, the lake, the temple, a small temple near by the quay, where people could do their offering to the saviour God,
and there, the archaeology provides elements which complete and analyse Strabo’s formulation concerning the peninsula of the Poseidon
dedicated to this saviour god, which was of a pristine importance, of course, for the Portus Magnus of Alexandria.
And, in this glass intaglio,
you can see here, Poseidon
And the lighthouse in between Isis and Poseidon, which were, of course, two major gods, Isis protecting the fleet.
and Poseidon, of course, the saviour god having a whole consecrated area on the peninsula which was in the centre of the royal quarters.
Thank you very much.