Alesia: where the siege was, and what was found there

A hill in the Côte-d’Or, in the commune of Alise-Sainte-Reine: Mont Auxois. At the top, a plateau of 97 hectares, which Michel Reddé ranks among the largest oppida of temperate Europe. Two rivers run along it, the Oze and the Ozerain, and the plain of Les Laumes opens below.

Read Caesar again. In McDevitte and Bohn’s English: “The town itself was situated on the top of a hill, in a very lofty position, so that it did not appear likely to be taken, except by a regular siege.” Two rivers washed the foot of the hill, a plain of about three miles lay before the town, and hills of equal height surrounded it. The ground answers point by point. And Alesia was no makeshift camp before the siege: excavation has shown an oppidum of La Tène D2 defended by a rampart of that date, with occupation levels going back to La Tène D1, and metalworkers’ workshops under what would become the Roman forum.

Summer 52 BC. Vercingetorix has just lost his cavalry in open country; he falls back on Alesia. Caesar arrives the next day, looks at the position, and decides not to attack. He digs. A first line facing the town, eleven Roman miles round, with twenty-three redoubts held day and night.

Then a second, turned outward, fourteen miles round, because a relief army is on its way. Between the two, his legions: besiegers on one side, besieged on the other. And buried traps with names out of a gardening catalogue: the cippi, the “lilies”, and what the English translation calls spurs, stakes a foot long with iron hooks, sunk in the ground at small intervals.

The figures are the winner’s: eighty thousand men shut in, food for thirty days at most, a relief army of eight thousand horse and some two hundred and forty thousand foot. There is no way to check them, and a general writing for the Senate has an interest in enlarging his enemy. What the earth has given back is the ditches, not the men.

The identification with Alise goes back to the end of the ninth century, and until 1855 it was accepted by everyone. Then, on 10 November 1855, Delacroix, the city architect of Besançon, argued before the Société d’Émulation du Doubs that the real Alesia was Alaise, in Franche-Comté. The debate was born five and a half years before the first spade went in, and it would last a century. Izernore in the Ain followed in 1862, Novalaise in Savoie in 1866, then Chaux-des-Crotenay in the Jura, defended from the late 1960s by André Berthier, a correspondent of the Institut and the excavator of Tiddis, in Algeria.

What finally settled it was not an argument from the text. As early as 1839 a stone found in the sanctuary of the god Ucuetis carried, in Gaulish, the name of the place: ALISIIA. The excavations of 1861-1865, then those of 1991-1997, produced the ditches, the weapons, the coins. Two sling bullets picked up in one camp even carry an engraved name, T. Labi, for Titus Labienus, Caesar’s lieutenant.

The quarrel does not die for all that, because it is no longer archaeological. Michel Reddé, who directed the Franco-German excavations, puts it plainly: this is certainly not, today, a relevant debate for an archaeologist. He explains it by an awkward fact: the excavations of Napoleon III, sound in their method, were not published until 1989, by Joël Le Gall. A century and a quarter of emptiness, into which suspicion moved.

From 1991 to 1997 a Franco-German team led by Michel Reddé and Siegmar von Schnurbein went over the whole circuit of Mont Auxois; the results appeared in 2001. The two concentric lines are there, as are the three families of traps Caesar describes (stimuli, lilia, cippi), and in the plain the ditch nearest the oppidum was in places filled with water, exactly as the text announces.

The ground does not recite Caesar, though. Where the book describes two ditches everywhere, the excavations find now two, now three, now only one; the towers stand between 15 and 40 metres apart depending on the sector. Reddé judges these gaps fairly secondary and recalls that Caesar writes in a mould: his lilies are a figure of rhetoric and not a technical term, and his dispositions follow a doctrine already written down in Philo of Byzantium and in Polybius.

Much remains to be done. Historians restore ten, even twelve legions before Alesia, and of the twenty-three forts Caesar announces, only three have been physically identified. Reddé calls for a large LIDAR programme; an aerial survey of that kind was carried out on the site in 2011.

The town did not die with the siege. It became a modest but well-equipped Gallo-Roman settlement: a square lined with shops and porticoes, a covered market, a theatre built from the Flavian period, a basilica in the second century, craftsmen’s quarters. Pliny mentions its bronzeworkers. The monument of Ucuetis, which the 1839 stone came from, is the building of the metalworkers’ guild and the sanctuary of their protecting deities; on the edge of the town, the spring sanctuary of Apollo Moritasgus was excavated from 2008 to 2018 by Olivier de Cazanove, who uncovered an exceptionally well-preserved wooden basin.

West of Mont Auxois, the sheet-copper Gaul looking out over the plain dates from 1865, not from 52 BC: it is the statue commissioned by Napoleon III, drawn by Viollet-le-Duc and sculpted by Aimé Millet, and its story is told in the Vercingetorix dossier. Below, in the plain of Les Laumes, the MuséoParc Alésia takes visitors through reconstructed Roman fortifications; the remains of the ancient town are three kilometres further up.