French team uses digital scanners to produce amazing 3D reconstructions of destroyed or damaged historic buildings
Can technology help restore Syria's lost archaeological heritage?
For 3,000 years, the finely-carved basalt stone lions had guarded the temple of Ain Dara, to the north west of Aleppo. It took just a few seconds for a series of explosions late last month to reduce many of them to a heap of rubble.
Syrian officials blamed Turkish forces fighting Kurdish militias in the region. Turkey denies it targets archaeological sites. No matter who is to blame, it seems another part of Syria’s extraordinary heritage has been shattered; a lengthening roll call of archaeological vandalism that includes the historic centres of Aleppo and Homs, the Crac des Chevaliers medieval castle and Palmyra, the complex of temples and tombs that felt the full fury of ISIL.
Even as the fighting continues, examining what remains and deciding how best to restore is at the heart of debates among archaeologists.
And while the heart may say everything should be put back as it was, the reality is that in many cases this will be impossible.
“Sometimes it is possible and sometimes it is not,” reflects Jacques Seigne, an architect and former director of the French Archaeological Mission at Jerash in Jordan. “We may have some philosophical position about restoration. To restore, or not to restore.”
Mr Seigne has visited Syria twice in the last year, visiting Palmyra after it was first liberated with help from Russia and then again, more recently, after it was re-occupied by ISIL until they were driven out for a second time.
His verdict? "There is very important damage. And in some cases totally irreversible.”
One example is the structure known as the Tomb of the Three Brothers, its interior covered in exquisite and beautifully-preserved wall paintings from the second century.
Or rather it was. At some time during their occupation, ISIL fighters used the interior as a base. They also covered the walls in a thick layer of white acrylic paint.
“The kind of acrylic paint is a modern one and unfortunately the ancient painting is not strong enough to be restored,” says Mr Seigne. “It will not be possible.”
Of the Tetrapylon, the four sets of four columns at the heart of the site and dynamited a year ago, he said: “It is out totally out. The problem is that the stones are preserved, but they are not in very good condition.
The Temple of Bel, levelled in another explosion? “Totally blown up. It is unbelievable, terrible. It cannot be restored as it was.”
It sounds like a grim obituary for a country the French expert describes as “an open air museum”. But Mr Seigne has not visited Syria just to mourn, as he explained on a visit to the Paris-Sorbonne campus in Abu Dhabi recently.
He was joined by Bruno Deslandes, the director of Art Graphique & Patrimoine, a French company using cutting-edge technology to document what has survived – and what can be preserved.
Mr Deslande and his team use mobile 3D scanners on site for their work. Over 10 minutes, the cameras rotate 360 degrees collecting around 470 million measurements. To create a complete picture, each scanner will be moved hundreds of times for a single site.
The results are extraordinarily accurate surveys that can be processed back in Paris to create a virtual recreation, one that can be studied from any angle. So far he has visited four sites in Aleppo, the crypt of the Church of the Holy Belt in Homs, and of course, Palmyra.
At Palmyra, they studied one part of the Temple of Bel that apparently miraculously survived the destruction. The gateway to the temple still stands, but as the 3D images showed, perhaps for not much longer.
“There are cracks in the columns,” says Mr Deslandes. “It is not supported by any foundations. It is moving and it could collapse.”
By studying the profiles created by the scanners, it is possible to decide where immediate intervention is needed.
It is too early to speak about restoration right now, he says. “We are looking at emergency interventions based on the data we have collected to avoid more damage.”
Of course not all the problems faced by archaeologists today are technical. During past conflicts, including the American invasion of Iraq, they could still monitor historically sensitive sites.
But the destruction of the Buddhas of Bamiyan in Afghanistan by the Taliban in 2001 ushered in a new era of destruction of the past - one that was ideological rather than accidental.
Recording what remains at least creates a permanent record for the future. By coincidence, the paintings from the Tomb of the Three Brothers had been photographed in every detail before the war for a book to be published shortly.
The Monumental Arch at Palmyra was also destroyed by ISIL. A one-third-sized replacement was created by the Institute of Digital Archaeology, but the task was difficult because no detailed survey had ever been done of the structure.
Or so it was assumed. Now one has just turned up in Paris, carried out not by historians, but by a French architect in 1988, acting under instructions from former French president Francois Mitterrand, who wanted an exhibition on famous arches to commemorate the opening of his own 110-metre Grande Arche in the city’s new business district, La Défense.
Sometimes, Mr Seigne says, the problem is simply locating the recordings that have already been made.
The French archaeologist remains pragmatic about what can be done for the future. “With restoration you have to make a balance with the cost, and what you get from the cost.
“Also, very frankly, it is a question of what is urgent for Syria. The restoration of monuments? Hmm. They have no more water, no more electricity, no more hospitals, schools are destroyed, a lot of things are destroyed.
“So it is much more important to make choices and, very frankly? I like archaeology, I spent my life in archaeology, but if I had to give advice – archaeology can wait.”
Many of the structures destroyed or badly damaged by extremists were in fact earlier reconstructions by previous generations of archaeologists. The Temple of Bel is one example. It was just one of several temples to the Babylonian god at Palmyra.
French archaeologists worked on the site until 1938. “Lots of columns were ready to be restored, but it was stopped because of the Second World War. Maybe, if not for the war, the Temple of Bel would have many more columns.
As the rebuilding of ISIL-desecrated Iraq begins, what will happen to its cultural heritage sites?
“Some are in good condition, ready for restoration. So it could be possible to restore another Temple of Bel if we want to. “
Both men agree it will take time. “We need to have priorities,” says Mr Deslandes. “In Aleppo it makes sense because the old city is the economic heart, so by restoring you are initiating a process of revitalising.
"This is not the case in Palmyra.”
Mr Seignes has another perspective on the ancient site. “We have to keep it as it is. It shows what happened. It is the face of the history of Palmyra.
“The Romans came once. Time is passing. This is history and I think it is better to keep it as it is and wait. Eventually in the future maybe we can restore it. If not, khalas, we close the door.”