What will future archaeologists make of our most cherished cultural objects? Eric Cline answers this question and more in his history of the discipline

Former glories: excavating Ebla, one of Syria’s oldest sites James L. Stanfield/National Geographic Creative

WHAT would an archaeologist digging in the remains of our cities two millennia from now make of our civilisation?

That’s a fine question, posed by long-time US archaeologist Eric Cline in the stimulating epilogue to his new book, Three Stones Make a Wall. Assuming that our noticeboards and signposts, if not our long-vanished emails and websites, are still decipherable in AD 4000, most large urban structures, such as highways, bridges, schools and even archaeological museums, should be easy enough to figure out.

And what of the still more puzzling shrines or temples “complete with a goddess wearing a crown and with flowing locks”, located on virtually every street corner? “I think there is a good chance of misidentifying Starbucks as a religion,” jokes Cline. After all, a religious purpose is the typical explanation put forward by today’s archaeologists for anything incomprehensible that they find in ancient ruins.

Most of Cline’s book deals with the stories of dramatic discoveries since archaeological excavation became methodical, beginning at Herculaneum and Pompeii in the 18th century. These are selected from around the Mediterranean and a few other parts of Europe, the Americas, Egypt and the Middle East, with occasional forays into the rest of Africa and Asia. For reasons that aren’t explained, Russia, the Indian subcontinent, Japan, Australia and Polynesia don’t feature.

Interwoven with these stories are the careers and colourful personalities of some well-known archaeologists, such as Heinrich Schliemann at Troy and Mycenae, Arthur Evans at Knossos, Howard Carter at Tutankhamun’s tomb, Leonard Woolley at Ur, and the Leakey family in east Africa. There are some more recent pioneers too: underwater archaeologist George Bass, the excavator of Bronze Age shipwrecks in the Mediterranean, and David Stuart, Mayan script decipherer and the youngest person to receive a MacArthur Fellowship, at just 18.

“What of the puzzling shrines or temples with a goddess wearing a crown, on every street corner?”

Both the discoveries and the discoverers are illuminated by gritty fieldwork recounted from Cline’s experience at sites around the eastern Mediterranean, such as the ancient city of Megiddo in Israel, known as Armageddon to the Greeks. This area was the focus of his valuable 2014 book about the Bronze Age, 1177 BC: The year civilization collapsed.

The mix is an enjoyable and wide-ranging one. That said, the most original and clearly scientific sections of Three Stones Make a Wall are four chapters prompted by the questions non-archaeologists are wont to ask. How do you know where to dig? How do you know how to dig? How old is this and why it is it preserved? Do you get to keep what you find?

Cline patiently explains. Where to dig depends on the surveying methods. These range from people on foot fanatically scouring areas for artefacts, to aircraft scanning jungle terrain using aircraft equipped with laser tech (lidar), to the sophisticated interpretation of satellite images by individual archaeologists.

In 2010, for example, Cline and fellow academic Sarah Parcak purchased some Quickbird satellite imagery of the area around Tel Megiddo. “Almost immediately,” writes Cline, “we saw the outlines of what looked like a large building in a field right next the ancient mound.” The images had pinpointed the exact spot Israeli archaeologist Yotam Tepper had earlier proposed as the probable location of the camp of the sixth Roman legion during the 2nd century AD.

The two also found “an almost perfect match with other Roman camps”, like those built around the hilltop site of Masada, a fortress besieged by the Romans around AD 73. They shared the images with Tepper and his collaborator, who carried out remote-sensing of the site at Tel Megiddo, including ground-penetrating radar and electromagnetic surveys. Subsequent excavations revealed Roman-period coins, pieces of armour and roof tiles stamped with insignia of the sixth legion: it was definitely their camp.

As for the dating of artefacts, Cline rattles through radiocarbon and potassium-argon analysis, rehydroxylation, pottery typology, thermoluminescence and dendrochronology. However, he stresses, archaeologists must admit “a willingness to acknowledge that none of it is fixed in stone”.

For example, rehydroxylation can estimate the age of pottery on the basis of the rate at which it absorbs water after its original firing. But when it was applied to a medieval brick from the UK city of Canterbury, it gave an age of about 66 years. The brick turned out to have been accidentally re-fired when Canterbury was bombed in the second world war.

As for the question of who keeps what, finders are no longer keepers. “Not only don’t I get to keep what I find,” observes Cline, “I don’t think that other people should collect such items either.” The consensus among scholars, he says, is that there is a direct correlation between private collecting and the looting of ancient sites – as the recent destruction of ancient Syrian sites by ISIS shows so painfully.

It is difficult to disagree. And yet, how very much poorer would the world’s great archaeological museums be without the past donations of private (and often none too scrupulous) collectors.

Three Stones Make a Wall: The story of archaeology Eric H. Cline Princeton University Press

This article appeared in print under the headline “Raiders of the lost phone”