Having been established between 8,000 to 10,000BC, Damascus is believed to be the world's oldest continuously inhabited city. The old walled city feels especially ancient, with its narrow, smooth-walled alleys punctuated by enigmatic doors leading to the blank-faced houses' pleasing, verdant interior courtyards. It has a population of around 4 million. The Souq al-Hamidiyya, a tangle of streets packed with tiny shops, is entered through columns from a Roman temple built on a site that had been occupied by an even older temple. The souqs themselves smell of cumin and other distinctive spices and you can find passages dedicated to everything from leather and copper goods to inlaid boxes and silk scarves. At the other end of Souq al-Hamidiyya is a fort-like section of the extant city wall that is the Citadel (but make sure to visit Aleppo's Citadel for a truly amazing experience). Nearby, you can visit the mausoleum of Salah al-Din, known in the west as Saladin, the chief anti-crusader. There's a great statue of him on horseback right next to the citadel which will make you gasp if you walk all the way around it - underneath the horse's slightly lifted tail sit two dejected Frankish knights, one of whom is holding a shield with a lion on it.