Aleppo before the war: a photo taken in 2001, when no-one suspected the suffering and destruction the city would experience barely a decade later. It shows Aleppo's citadel peacefully overlooking the Old Town bathed in a golden light. At the time, the minaret of the Great Mosque had just been scaffolded for renovation

One of the most ancient mosques in the world: the Umayyad Mosque of Damascus is one of the oldest mosques in the world, having been built at the beginning of the 8th century. The mosque is located in the historic Old Town, which has been a UNESCO World Heritage Site since 1980

Palmyra's Valley of the Tombs: when the ancient cultural and trading city of Palmyra became a UNESCO World Cultural Heritage site in 1980, its primary temple became a major archaeological site. The reliefs and architectural elements pictured above are from a temple tomb excavated between 1981 and 1985 in a joint initiative presided over by the German Archaeological Institute and the Syrian Directorate of Antiquities

The ancient Temple of Baal: the more than 2,000-year-old temple that was consecrated in honour of the Mesopotamian god Baal was a highly preserved ruin in the oasis town of Palmyra before the war. However its central building – the cella – and its sanctuaries were blown up by Islamic State in 2015

Rubble around the Citadel of Aleppo: the ancient Citadel of Aleppo, which rose to its peak during the 12th and 13th centuries, is one of the oldest fortresses in the world and has been a UNESCO World Heritage Site since 1986. The war destroyed the surroundings and parts of the citadel. In the meantime, however, it can be visited again

Former glory: this photo shows the intact surroundings of the celebrated citadel complex – with origins going back to the 3rd millenium BC – before the war. The mosque complex dating from the 13th century, which is located directly in front of the Citadel of Aleppo, was heavily damaged when the Syrian Army used it as a military base

Aleppo's world-famous bazaar: with more than 1,000 small shops, Aleppo's old bazaar, or souk, was the heart of the storied Syrian city – the largest by population in the country before the civil war began. But the Syrian conflict destroyed much of the old city where the bazaar is located, and large parts of the labyrinthine structure remain devastated today

The ruins of the conflict: Aleppo has become a symbol of Syria's civil war. Large parts of the once flourishing metropolis, Syria's former economic powerhouse, are no longer recognisable. The large Waqf complex of the Abshir Pasha mosque (left), and the Behramiyah mosque (right) in the historic Al-Jdayde district suffered catastrophic damage during the conflict