Reports indicate that Islamic State militants in Syria have captured Palmyra, a famous, ancient Roman-era city and a UNESCO World Heritage site. On Wednesday, they seized part of the town of Tadmur, which is adjacent to the ruined city. That's a huge concern, given the extremist group's penchant for smashing pre-Islamic antiquities as well as icons and shrines it considers blasphemous.

According to the BBC last week, Islamic State militants were just a bit more than a mile away from the archaeological complex after a lightning advance through the desert. Rights groups said the extremists executed 26 civilians, including 10 whom they beheaded, in nearby villages for supposedly collaborating with the regime of Syrian President Bashar al-Assad.

Now, their control of the area around Palmyra has expanded following the withdrawal of government forces.

"If [the Islamic State] enters Palmyra, it will spell its destruction," Syria's head of antiquities, Mamoun Abdulkarim, told Agence France-Presse last week. "If the ancient city falls, it will be an international catastrophe."

The Islamic State says it has taken full control Palmyra, a UNESCO World Heritage site in Syria, just days after capturing Ramadi, a provincial capital in Iraq. (Reuters)

The brutal Syrian civil war, which has claimed hundreds of thousands of lives and led to the hollowing out of its cities, has also taken a toll on the country's rich architectural patrimony. The Citadel of Aleppo, a historic fortress in the heart of Syria's war-ravaged business capital, has suffered bombings and clashes between rebel and regime forces; militias have also set about occupying medieval Crusader castles.

Palmyra, which is located in the center of Syria, was an old oasis town that turned into an influential desert crossroads for around the first century A.D., at a time of significant Roman influence in the Near East. Its architecture and artifacts reflect its place as a meeting point between civilizations and cultures. Some of Palmyra's major structures are considered to be among the best-preserved examples of Roman antiquity.

Here is UNESCO's description of the site:

It grew steadily in importance as a city on the trade route linking Persia, India and China with the Roman Empire, marking the crossroads of several civilisations in the ancient world. A grand, colonnaded street of 1100 metres' length forms the monumental axis of the city, which together with secondary colonnaded cross streets links the major public monuments including the Temple of Ba'al, Diocletian's Camp, the Agora, Theatre, other temples and urban quarters. Architectural ornament including unique examples of funerary sculpture unites the forms of Greco-roman art with indigenous elements and Persian influences in a strongly original style. Outside the city's walls are remains of a Roman aqueduct and immense necropolises.

Syria is a land rich in antiquities, but Palmyra is perhaps its jewel. In the 18th century, European travel accounts and etchings of the city's splendor inflamed the imagination of Enlightenment thinkers. The legend of Queen Zenobia, a 3rd century Palmyrene ruler who led a revolt against Rome, was the subject of centuries of Western poetry and literature.

Anti-government forces briefly held the site in 2013, before it was recaptured by the regime. Last year, the New York Times found the Temple of Bel, a 2,000-year-old structure that is the city's most famous, to be intact despite carrying the scars of bullet and mortar fire.

In the past year, the Islamic State's fighters have gleefully posted videos of their destruction of ancient Mesopotamian ruins and antiquities in the environs of the Iraqi city of Mosul. They laid explosives and detonated buildings at Nimrud, a city that dates to the 13th century B.C. And they set upon the fortress town of Hatra, once guarded by the successors of Alexander the Great, with sledgehammers and pickaxes.

The fears of what may follow should they fully seize Palmyra are more than justified.

This post has been updated.

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