Hama's most distinctive attractions are its norias, wooden water wheels up to 20m in diameter (the equivalent in height of a four- or five-storey building), which have graced the town for centuries. The land around the Orontes is considerably higher than the river itself, which is deeply incised into its rocky bed, making it hard to irrigate. The norias were constructed to scoop water from the river and deposit it into aqueducts, which then channelled it to nearby fields and gardens.
There have been norias in Hama since at least the 5th century AD, as attested by a mosaic displayed in Hama's new museum, but the wheels seen today are the design of the 13th-centruy Ayyubids, who built around 30 of the things. Of these, 17 norias survive, dotted along the course of the river as it passes through town, although all have been reconditioned and/or rebuilt during the late Mamluk and Ottoman times. The norias still turn, but only during spring and summer; at other times the waters of the river are diverted into more modern irrigation schemes elsewhere, reducing water supplies.
About 1km west of the centre, is the largest of the norias, known as Al-Mohammediyya. It dates from the 14th century and used to supply the Grand Mosque with water. Part of its old aqueduct still spans the road. Beside the noria there is a small stone footbridge that crosses the river and leads to another bit of parkland and an open-air coffeehouse.