Syria’s northern city of Aleppo was once a thriving commercial hub with a proud history dating back millennia. Since the Syrian civil war began in 2011, much of the city has been devastated by intense shelling and airstrikes.

As government forces work to wrest back control of Aleppo from an armed rebellion, which is battling against the Assad family’s 40-year rule, aid groups are cautioning that civilians have fewer places to go while their city gets hammered. The U.N. human rights office said Tuesday that government forces had killed at least 82 civilians in the eastern neighborhoods, reported the AFP.

“The worst humanitarian tragedy of the 21st century is unfolding before our eyes,” said France’s U.N. Ambassador Francois Delattre, according to the Associated Press.

“It will never be rebuilt in the same way. It will never be this living museum at the crossroads of civilization.” — correspondent Courtney Kealy

Overall, more than 250,000 people have died in the five-year conflict, and repeated attempts to broker a cease-fire have failed.

Courtney Kealy, a television and radio correspondent now based in New York, remembers visiting Syria for the first time in 1999 to do a travel piece for the New York Times.

She covered a Sufi concert in an 8th century palace, watched artisans hand print designs on fabric and bought strands of natural pearls for her family.

Aleppo epitomized Syria’s place on the Silk Road ancient trading route. “The souk (open-air market) was so narrow that you could only send goods through by donkey. You just felt like you’d stepped into another century.”

Now, looking at the images of the destruction is heartbreaking, Kealy says. “It will never be rebuilt in the same way. It will never be this living museum at the crossroads of civilization.”

Reuters photographers have documented the city before and after the war began, in these 2009 images and others taken in the past few days.

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