Deep in the Nile delta, on the outskirts of the village of Qantir, 60 miles north-east of Cairo, a pair of giant stone feet stand in a field of lush green wheat. They belong to a broken statue of the Pharaoh Rameses II. And the field belongs to a farmer, Muhammad Said Awad. "Whenever you put the plough in the earth," he says, "it just keeps hitting old stones."
A few metres from the feet lies an arm and, beyond that, an inscribed column base. Archaeologists believe these remains were part of a vast ancient capital called Pyramisa, built by Rameses, which now lies just 10cm below ground.
At the International Congress of Egyptologists in Cairo yesterday, antiquities authorities warned that archaeological sites across the delta are under threat from rising ground water and Egypt's expanding population.
"They're in dire danger," said Gaballah Ali Gaballah, the secretary general of Egypt's Supreme Council of Antiquities. "Unless we do something about them urgently, we are going to lose them for ever."
Edgar Pusch, the leader of a German team working on the Pyramisa project, said: "Everywhere you see is pure archaeology. The problem is that most of the land is in private hands, and is being used for agriculture, and ploughing this land means destroying archaeological and cultural layers. But what can you do?"
At yesterday's 1,000-strong meeting, officials urged the establishment of a "salvage campaign" for the monuments of the delta, Egypt's ancient gateway to the Mediterranean. Archaeologists in Egypt have traditionally neglected the delta, preferring to dig in the desert and the dry south of the country, known as Upper Egypt, which have yielded spectacular discoveries: the tomb of Tutankhamun, for example, and, more recently, golden mummies found at the oasis of Bahariya in the Western Desert. Monuments discovered in sandy areas tend to be better preserved than those that lie beneath the delta's rich agricultural soil.
Digging in the delta is also more costly, because it often requires pumping water away first. But ground water is now eating away at the monuments, and Egyptian archaeologists say they will insist, in the future, that those who want to work in Egypt dig in the delta, before it is too late.
Since Mr Pusch began excavating at the site of Pyramisa in 1980, the village of Qantir has doubled in size, expanding, he believes, over Rameses' palace. While he is using electronic equipment to analyse the site, he is conscious of the race against time. Close to the feet of the broken statue, yet another new house is going up.
Casually examining what looks like a small pile of rubble beside the house, Mr Pusch stumbles on what he believes to be a tethering stone from a stable built by Rameses for horses used to pull the Pharaonic chariots. "We have to do everything we can to protect this area and excavate before it's too late."
His fellow archaeologists acknowledge they have ignored the delta for too long. "We're losing tons of Egyptian history by not working there," said Salima Ikram, a Pakistani archaeologist working at the American University of Cairo. "There are some marvellous sites that haven't been explored that could give us new ideas or change how we think about Egyptian history. One might prefer to work in Upper Egypt but, in terms of saving the heritage, the Nile delta is absolutely crucial."