Archaeologists have made a remarkable discovery beneath the world's oldest city, unearthing an extensive network of ancient canals.
The vast irrigation system was found underneath Eridu in southern Mesopotamia, in present-day Iraq.
Dating back to before the first millennium BC, the discovery sheds new light on how early farmers irrigated their fields.
Eridu, believed to be around 5,400 years old and abandoned in 600 BC, is one of the best-preserved ancient archaeological sites.
The remnants of canals were found
Jaafar Jotheri et al, Antiquity/Durham University
Researchers identified nearly 200 primary canals directly connected to the ancient Euphrates river. These were complemented by approximately 4,000 smaller branch canals.
Together, this intricate water system fed over 700 farms throughout the region. The main canals ranged between 1-9km in length and 2-5 metres in width.
This sophisticated irrigation network required significant labour and expertise to maintain. The system evolved over centuries, with different parts of the network likely used at different times.
Ancient farmers in Eridu used the natural landscape to their advantage. They dug canals that allowed water from high river levees to flow by gravity to surrounding fields.
The irrigation canal was found near Eridu
Jaafar Jotheri et al, Antiquity/Durham University
Breaks in the levees helped distribute water across the floodplain. Crops were planted on both sides of the Euphrates.
"Both sides of the river were canalised and farmed, although farmers exploited the northern side more heavily than the southern side," the researchers wrote.
This ingenious system demonstrated the advanced agricultural knowledge of these early civilisations.
The canal network remained remarkably well-preserved for centuries due to a shift in the Euphrates river's course.
This change occurred in the first millennium BC, leaving the area dry and uninhabited. Unlike other parts of Mesopotamia where older irrigation systems were buried under newer canals, Eridu's ancient landscape was preserved.
This unique preservation has given archaeologists an unprecedented glimpse into ancient farming techniques. The research was led by geoarchaeologist Jaafar Jotheri from Durham University.
Researchers employed a combination of satellite and drone imagery to identify the ancient canal network.
This high-tech approach was complemented by extensive fieldwork on the ground.
