Africa 3 June 2016 Ancient Egypt’s perfectly preserved underwater cities, and how they were discovered Two sunken cities have been found at the mouth of the river Nile. Image: Franck Goddio / Hilti Foundation - Photo: Christoph Ger igk Sign UpGet the New Statesman's Morning Call email. Sign-up Two ancient cities have been discovered, perfectly preserved, at the bottom of the Nile. But how do you go about finding a lost city (or two)? Dr Damian Robinson, director of the Oxford Centre for Maritime Archaeology, is a member of the discovery team. The treasures he and his team found are the subject of a new exhibition, Sunken Cities: Egypt’s Lost Worlds, at the British museum. “In 1933 a British RAF pilot flew over the Aboukir Bay and saw what he thought was remains under the water,” he tells me. “The pilot reported them to a local prince who sent a diver to investigate but nothing was found.” The Second World War and later the Cold War stopped any further exploration of these ruins until 2000, when archaeologist Franck Goddio of the Institut Européen d’Archólogie Sous-Marine entered the story. Image: Franck Goddio / Hilti Foundation - Photo: Christoph Gerigk With geo-sensing survey techniques, he measured different properties of the Earth’s surface and made a detailed map of the seabed. “Using a nuclear resonance magnetometer, specially developed by a French energy commission, he was able to measure the earth's magnetic field and variations in it caused by the local deposit geology.” The maps chronicled the sunken landscape and its main topographical features. The team began detailed investigations by zeroing in on areas that looked like they had a lot of potential for excavation. The two cities they rediscovered, the Egyptian city Thonis-Heracleion and the Greek city of Canopus, were built on unstable Nile clays. “They have a lot of water in them,” Robinson says. “The load of people caused the sediment to collapse, pushing the water out and causing people to abandon the city. This, in 800AD, was the first of two dramatic collapses, but the land itself didn’t fully sink until 1000 years later due to rising sea levels.” As the water was squeezed out of the sediment, the sand settled on the ruins, preserving them perfectly. But it didn't look like much at first glimpse. “[The recovery was] not as spectacular as you'd think because there’s so much sand,” Robinson recalls. “Visibility was also very poor because of algae that give the water a green tinge. So we can only go digging at specific times – now and in October.” And how did they date the relics? “Historically and scientifically – for dating the city itself – by pots and artefacts discovered because pottery changes each period and are massively studied. For ships, we did radiocarbon dating.” The team found 69 ships – the largest collection of ancient ships found to date. The importance of the Egyptian city make the discoveries all the more exciting. “It was an obligatory entry point for Greek ships when Greece was providing Egypt with mercenaries to help defend it. The two also swapped ideas about religion, equating many of their gods,” Robinson says. Thonis-Heracleion (or Heracleion for short), for example, was named after its Greek temple to Hercules. “The right to rule Egypt was established in this city by pharaohs going to the temple to receive a case that contained a contract or inventory of all the things he had to take care of on behalf of the office.” As the discoveries have been predominantly Egyptian until now, Robinson hopes they’ll find more of a Greek presence there too. So far though, the haul of religious artefacts is rich and is already broadening our knowledge of the time. “The resurrection of Osiris is a major festival period in Egyptian life. The ritual navigation of Osiris on a boat through the waterways was a major part of this. We discovered a local version of this done at Heracleion. We can tell entire stories just from the objects and the texts we found.” Stories of everyday life, however, have proven harder to piece together. Robinson tells me that ordinary houses were made of mud brick that have now decomposed. However, there are some glimpses into common rituals: “Athenian coin weights bought by a merchant and used as a thank you offering for the gods for safely bringing him into the port were deposited in the middle of the port.” Some of the treasures are enormous, with the statue of the god Hapi – the personification of the river Nile – standing at five metres tall, making him and the statues of the king and queen the biggest ever discovered. Image: Franck Goddio / Hilti Foundation - Photo: Christoph Gerigk Do the discoverers have any favourite findings? “Franck Goddio likes the black stele [a stone erected as a monument] inscribed with the decree of Saïs because it tells him the name of the city and things like how its taxation works. I like a series of small barges – about 30cm long that have lead models of the gods and are carved. They are ritual barges – replicas of those that floated along in processions. I like it because it talks about the boating traditions of these individuals.” Image: Franck Goddio / Hilti Foundation - Photo: Christoph Gerigk › Welcome to "Tax Freedom Day": the right's latest con Subscribe For more great writing from our award-winning journalists subscribe for just £1 per month!