National Geographic : 2012 Sep
• Head down, pipe in hand, Hüssen---a researcher with the German Archaeological Institute--- crosses the road and wades through the thick underbrush. Fi y yards from the road, he nearly misses a low dirt mound about three feet high and six feet across. Littered with flat white stones, it runs in an unnaturally straight line along the forest oor. Nearly 2,000 years ago this was the line that divided the Roman Empire from the rest of the world. Here in Germany the low mound is all that's le of a wall that once stood some ten feet tall, running hundreds of miles under the wary eyes of Roman soldiers in watchtowers. It would have been a shocking sight in the desolate wilderness, 630 miles north of Rome itself. " e wall here was plastered and paint- ed," Hüssen says. "Everything was square and precise. e Romans had a de nite idea of how things should be." Engineering students measur- ing another stretch of wall found one 31-mile section that curved just 36 inches. Hüssen faces north, the Roman Empire at his back. Two hundred yards away, just past a nar- row meadow torn up by wild boars and a rush- ing stream, the next hill rises like a green wall. "Here's the border," he says, "and on the other side is a wonderful view of nothing." A stunning network of walls, rivers, desert forts, and mountain watchtowers marks Rome's limits. At its peak in the second century . ., the empire sent soldiers to patrol a front that stretched from the Irish Sea to the Black Sea as well as across North Africa. Hadrian's Wall, in England, probably the best known segment, was named a UNESCO World Heritage site in 1987. In 2005 UNESCO estab- lished a combined site with the 342-mile German frontier. Preservation experts hope to add sites in 16 other countries. e international e ort may help answer a surprisingly tricky question: Why did the Romans build the walls? To protect a regime besieged by barbarians, or simply to establish the physical edge of the empire? e question isn't just academic. De ning and defending borders is a modern obsession too. As politicians have debated building a wall between the United States and Mexico and troops face o across the land-mine-strewn strip of ground between the two Koreas, the realities the Roman emperors faced are still with us. Understand- ing why the Romans were obsessed with their borders---and the role their obsession played in the decline of the empire---might help us better understand ourselves. . ., Rome expanded contin- ually for six centuries, transforming itself from a small Italian city-state in a rough neighborhood into the largest empire Europe would ever know. e emperor Trajan was an eager heir to this tradition of aggression. Between 101 and 117, he fought wars of conquest in present-day Ro- mania, Armenia, Iran, and Iraq, and he brutally suppressed Jewish revolts. Roman coins com- memorated his triumphs and conquests. When he died in 117, his territory stretched from the Persian Gulf to Scotland. He bequeathed B ouncing along a dusty Bavarian logging road, archaeologist Claus-Michael Hüssen keeps his eyes on the tree line to the le , searching for some familiar landmark in the thick forest. Suddenly he pulls the van over and gets out, pausing to pack tobacco into his pipe and consult a 1:50,000-scale survey map. BY ANDREW CURRY PHOTOGRAPHS BY ROBERT CLARK Andrew Curry, a Berlin-based journalist, frequently writes about history. Robert Clark covered the Staf- fordshire gold hoard in the November 2011 issue.