Any schoolboy will tell you that the history of the Roman empire can be divided into two clear categories: the interesting bits, such as the gladiators, catapults, battle formations and barbarians at the gate, and the tedium, such as the underfloor heating, the love poems and trying to remember which type of column was which. In The Empire Stops Here, a blend of travelogue, classical history and archeology, Philip Parker has applied a wheeze Molesworth would be proud of, creating a sweeping journey ­aro­und the Roman world that sticks almost entirely to the good stuff. He does this by travelling along the outer edge of the imperial project — the limites, or frontiers of Rome, that marked where the great civilisation stopped and hostile territory began. His quest through the imperial badlands of Europe, the Middle East and North Africa succeeds in throwing fresh light onto the story of Rome and its often lunatic fringes, while offering classically minded travellers a few fresh ideas for routes and discoveries of their own.

It’s certainly a mighty undertaking: at its longest, Rome’s frontier stretched fully 10,000km, running through 21 modern-day nations from the coast of Cumbria to the kasbah of Tangier. In some places the border was marked by a stone wall, in others by a line of wooden watchtowers, or simply by a defensible river, such as the Rhine, the Danube and the Euph­rates, or, to the south, by impassable deserts. A millennium and more since their final fall, little remains of the limites today but ruins and ­echoes. Parker tracks those traces down with exhaustive diligence, weaving his clockwise quest from Carlisle to the Moroccan coast into the ­elevant diplomatic and military histories.

Described in functional, pragmatic prose, his discoveries are often remarkable — a barracks below a noodle bar in Vienna, a forum in the swimwear section of a German department store, Turkish villagers living on top of an ancient water cistern “the size of a small cathedral” — as are his revelations of the lingering fingerprints of Rome on the modern world. Cologne’s street grid, for example, is sycophantically slanted to match the rising and setting sun on Emperor Augustus’s birthday.

Some nations emerge with considerable credit for the preservation of their classical past (this book certainly makes a holiday in search of Roman Germany a surprisingly exciting prospect) while others feel Parker’s scorn: post-communist Bulgaria stands accused of “one of Europe’s cultural disgraces” for allowing the looting of the ruined city of Ratiaria.

Previously unheralded sites also receive generous attention here — I shall certainly soon be visiting the fort at Anderitum (now Pevensey, in East Sussex), which Parker ­speculates may have been the last outpost the Romans abandoned when they let Britain fall, not unlike the roof of the Saigon embassy. (Apparently, having developed an early taste for dull prosperity, most of the southern English pleaded desperately not to be given their independence.) More adventurous ­classicists will be drawn to the chapter on Algeria, and the spectacular cities of Thamugadi, Tiddis and Cuicul, that Parker crosses unstable, insurgent territory to reach.

But sadly, such diligence does carry a cost. For while visiting every single column, arch or altar along the frontier may have been an admirable personal ambition, it proves something of an excessive literary one, bloating what should have been a nimble fighting manoeuvre of a travelogue into an unwieldy, slow-moving campaign, stretching to more than 500 pages from sea to sea. It also becomes hard not to conclude, relatively early in the journey, that Roman archeological sites should be placed, alongside sex and professional football, in that category of subjects that can be diverting to look at, but become unavoidably dull when described at length in prose. The damage done by Parker’s slightly obsessive cataloguing of amphitheatre capacities and wall heights is not fatal, however, for his historical writing, which ultimately constitutes the meat of the book, is sprightly and personable, with an eye for the eccentric.

Strange things, it emerges, once happened here in frontier country. New gods sprang to life when Roman deities merged with local idols, and lonely soldiers joined dark, secretive cults. Generals shunted to the furthest outposts often got ideas above their station, leading local rebellions against the emperor back in Rome. One such uprising, in Batavia (in the Netherlands) in AD69, led to frontier life getting a surreal twist — to prevent native troops from joining further local revolts, it was decreed that any volunteer force raised on one frontier had to serve on another, a reform that led to a unit of Syrian archers being sent to the limits of the Scottish Highlands, and a deployment of Britons getting an unlikely tour of the Transylvanian alps.

The most charismatic figures in Parker’s survey, however, lie on the other side of Rome’s barricades — the parade of tribes, clans and kingdoms that traded blows with the empire, from the Huns and Vandals, to the more obscure ethnicities such as the fearsome Blemmyes on the edges of Egypt, whom Pliny the Elder described as headless warriors, their faces protruding from their chests. Many of the empire’s supposedly implacable foes actually migrated towards the limites, to profit from what Parker describes as the “uneasy symbiosis” of convenient enemies. Attila the Hun, the barbaric “scourge of God”, was so enamoured of Roman civilisation that he once crossed the border to kidnap an architect, so he could bathe in the imperial manner. One Roman merchant, dragged into the badlands by the Huns, actually requested to stay on the “wrong” side of the barricades after his ransom had been paid, on the grounds that trading with savages involved so much less red tape than doing business with the empire.

Finally, of course, “the empire grew old”, its skin grew flawed and fragile, and those symbiotic enemies, rendered mighty by centuries of sparring with the limites, realised they now had more to gain from Rome’s fall than from its survival, and rushed the barricades, leaving only Parker’s ruins. And for Parker, what begins as a journey through the glory that was Rome actually ends, via a dense, arduous but ultimately illuminating read, in a celebration of barbarism: the weirdness, diversity and pride that faced the empire across its walls and trenches, and that finally triumphed.

The Empire Stops Here by Philip Parker
Cape £25 pp656

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