Children leapt into the water from the long bridge linking the opposite banks of the river and swam ashore. One of them remained sitting cross-legged on the bank. He took some large pebbles from his pocket and tossed them one by one into the centre of the river. After he departed, shadows from the hills of the mediaeval town lengthened and merged as twilight fell. The river is the Tigris. A myth concerning this name, which means tiger, is told about the god Dionysus, who fell desperately in love with the nymph Alphesiobia. She fled from him, at which Dionysus turned himself into a tiger and chased her. The name of the medieval town is Hasankeyf, from the Arabic Hisn Kayfa meaning 'rock fortress,' since it stands on a great rock one hundred metres in height. The Turkish version of the name has inspired its own legend, according to which a youth called Hasan was sentenced to life imprisonment in the castle by one of the sultans.

One day when the sultan was in a good mood (keyf) he spoke to Hasan and asked if he wanted anything, upon which Hasan said he would like a horse to ride within the castle walls. The sultan provided the horse and Hasan spurred it into a gallop, leapt over the walls and plunged into the river below. The horse died in the fall but Hasan swam to freedom. Hasankeyf is situated in the Turkish province of Batman. Attempts are still being made to find a way to save the town from the rising waters of the Ilisu Dam. Still standing in the middle of the river are the remains of the medieval bridge which has withstood natural disasters and human ravages for so many centuries. The town perched on a natural fortress of rock which was first used by the Romans, and six thousand cave habitations hollowed out of the rock seem to whisper their ancient story to the wind which blows from the oil-rich Raman Mountains to the north.

Just below it are the remains of a small palace in the form of a tower with two lions carved in relief on its northern façade that is one of the first buildings constructed at Hasankeyf by the Ayyubids. Further down are the other surviving Ayyubid monuments: a minaret whose shaft contains two separate spiral staircases belonging to the ruined El-Rizk mosque, Sultan Süleyman Mosque, and Koç Mosque with its remarkable plasterwork decoration. All of them can be seen in turn as you climb the winding road towards the hilltop, greeting you on your journey back in time. You pass the castle gates, a caravanserai called Yolgeçen Han that is now a café, and innumerable caves.

The cry of a hoopoe is heard from the opposite bank of the Tigris, as if reminding you of the monuments there. One of these is the turquoise tiled mauseoleum of Zeynel Bey son of Uzun Hasan, which is the only Akkoyunlu structure remaining here, and another the Imam Abdullah Zaviye, a dervish lodge whose date of construction is unknown. Hasankeyf was a centre of learning in Mesopotamia, with its medrese or college, observatory, hospital and other institutions. Eb-ul Ýz El-Cezeri, an Artukid scholar and engineer celebrated for his Book of Automatons, studied and taught here. Cezeri might be described as the first cyberneticist, since he designed clocks and machines in the form of people and animals that worked on hydraulic principles, and presented these early robots to the Artukid sultan. The first studies of Hasankeyf were carried out in 1940 by the French archaeologist and architectural historian Albert Gabriel, who also took the first photographs of the monuments here and published his findings in Paris. In 1978 the town became a first grade conservation site.