News - Ancient Saharan empire thrived thanks to rare system of tunnels, study reveals

The Sahara Desert, a stretch of sand about the size of the United States, is an extremely forbidding land. With temperatures as high as 136 degrees Fahrenheit (58 degrees Celsius), it is one of the hottest places on Earth. Yet, despite the inhospitable conditions, an empire the size of Germany once flourished amongst the windswept dunes. Its survival was made possible by a novel technology: an underground tunnel system. The ascendancy of the civilization, known as the Garamantian Empire, was “remarkable given a climate comparable to the modern-day Libyan Sahara Desert,” according to new research presented to the Geological Society of America. The Garamantians occupied a southern swath of modern-day Libya and Algeria between 400 BC and 400 AD, researchers said. “The Empire was focused on a main City Germa at the base of a large escarpment,” Frank Schwartz, a professor at The Ohio State University, told McClatchy News. The Garamantians, the first urban society to appear in a riverless desert, survived using tunnels known as foggaras. These were hand-dug subterranean channels that, much like aqueducts, used gravity to deliver water from aquifers to agricultural areas. This method, though, proved unsustainable as the aquifer’s water levels eventually fell below the foggaras’ intake. As their water supply gave out, and geopolitical conditions changed, the Garamantians’ luck ran out around 400 AD, researchers said.