SAUDI ARABIA -- SITES PINPOINTED BUT RULERS HOSTILE TO INVESTIGATION

David Kennedy, a professor of classics and ancient history at the University of Western Australia, used Google Earth satellite maps to pinpoint 1,977 potential archaeological sites, including 1,082 teardrop shaped stone tombs.

"I've never been to Saudi Arabia," Dr Kennedy said. "It's not the easiest country to break into."

Dr Kennedy told New Scientist that he had verified the images showed actual archaeological sites by asking a friend working in the Kingdom to photograph the locations.

Few archaeologists have been given access to Saudi Arabia, which has long been hostile to the discipline. Hardline clerics in the kingdom fear that it might focus attention on the civilizations which flourished there before the rise of Islam – and thus, in the long term, undermine the state religion. In 1994, a council of Saudi clerics was reported to have issued an edict asserting that preserving historical sites "could lead to polytheism and idolatry" – both punishable, under the Kingdom's laws, by death.

Saudi Arabia's rulers have, in recent years, allowed archaeologists to excavate some sites, including the spectacular but little-known ruins of Maidan Saleh, a 2,000 old city which marked the southern limits of the powerful Nabataean civilisation.

For the most part, though, access to ancient sites has been severely restricted.