Hannibal's Route Across the Alps

Hannibal's most famous exploit was to cross the Alps with elephants, to invade Rome.

The route that Hannibal took across the Alps is unclear from the historical account. However, a well-argued case can be made for the most likely route. This route was first identified by Peter Connolly in his book Hannibal and the Enemies of Rome (1978 London) and the justification for the choice of route is described in more detail in an excellent article by Jona Lendering - some of which is used (with permission) below.


There are two ancient texts that give a description of Hannibal's route. The oldest is in the third book of the World history by the Greek historian Polybius of Megalopolis (ca.200-118 BCE). Polybius writes that:

"I have questioned men who were actually present on these occasions about the circumstances, have personally explored the country, and have crossed the Alps myself to obtain first-hand information and evidence" (World history, 3.48.2).

The other source is the twenty-first book of the History of Rome from its foundation, written by Polybius' Roman colleague Titus Livius of Padua, to English readers better known as Livy (59 BCE-17 CE). Both texts can be found here.

Livy and Polybius indirectly used the same eyewitness account. This may have been written by one of Hannibal's companions, Sosylus of Lacedaemon, who wrote a history of the Second Punic War in seven books. Probably Polybius used the original text; Livy knew it indirectly. His real source cannot be identified, but we can be confident that this anonymous intermediary was a careful author, who copied all the chronological indications he found in the eyewitness report. Livy's chronology is quite  precise, with the journey taking 16 days.

Day 1	March to the foothills; first encounters
Night	Camp on fairly level ground
Day 2	Moves towards blocked pass
Night	Attack on abandoned blockade
Day 3	Enemy attack on baggage train; capture of fortified enemy town
Night	Camp in enemy town
Day 4	Easy march towards the main pass
Night	Not mentioned
Day 5	Easy march towards the main pass
Night	Not mentioned
Day 6	Easy march towards the main pass
Night	Not mentioned
Day 7	Envoys from mountain tribe; their ambush
Night	Hannibal's infantry separated from cavalry and baggage train
Day 8	Hannibal's army reunited; continued march towards the main pass
Night	Not mentioned
Day 9	Hannibal's army reaches the main pass
Night	On the summit
Day 10	Halt on the summit
Night	On the summit
Day 11	Halt on the summit; it begins to snow
Night	On the summit
Day 12	Precipitous, narrow, and slippery descent; landslide
Night	Camp on the ridge
Day 13	Building a road
Night	Camp below the snow-line
Day 14	Building a road for the elephants; infantry descends
Night	At least two camps below the snow-line
Day 15	Building a road for the elephants; infantry descends
Night	At least two camps below the snow-line
Day 16	Infantry reaches plain; first of three days' rest to recover from fatigue

The problem is that Polybius' account suggests a northerly route whereas Livy's account is more likely to be a southerly route.

Another approach of the problem is to look at the passes in the Alps, and to find out which one suits the texts best. From north to south, these passes are:

1. Col du Petit Saint Bernard; this route has been advocated by Barthold Niebuhr, Theodor Mommsen, Lehmann, Viedebrandt, H. Kiepert and Francis de Conninck
2. Mont Cenis; advocated by Napoleon Bonaparte and H. Nissen
3. Col du Clapier; advocated by Perrin, Azan, Collins and Wilkinson
4. Col du Mont Genèvre; advocated by Neumann, Fuchs, Gaetano de Sanctis and Peter Connolly
5. Col de la Croix
6. Col de la Traversette: advocated by Sir Gavin de Beer and A. Guilleaume

The most likely pass is the one that would suit the following pieces of information, on which Polybius and Livy agree:

1. The pass has to offer sufficient room to build a camp for at least 20,000 soldiers, 6,000 knights and thirty seven elephants (the number of men that would reach Italy);
2. The defile should begin within 15 to 30 kilometers from the summit, because Hannibal's soldiers started to climb down on the day they left the camp on the summit.
3. The road to Italy must be in a northerly direction: the soldiers encountered snows of the previous year when they were descending.
4. The first part of the descent has to be narrow and steep.
5. After this, the descent has to be less steep for about 50 kilometers, because it took Hannibal's men three days to reach the plain.
6. Italy should be visible from the summit (according to Polybius) or from a point at the beginning of the precipitous descent (according to Livy), because Hannibal was able to show his men the plain during a speech (although this may well be a later, literary invention).

Only one pass that fits all the conditions is the lowest, the Col du Mont Genèvre between Briançon in France and Susa in Italy. This route would also correspond to the distances mentioned by Polybius (252 kilometers from the Rhône to the beginning of the ascent, and from there to the plain of the Po 216 kilometers).

The picture shows the ascent to the Col du Mont Genèvre, some kilometers beyond Briançon as it looked in May 1993.


Assuming this route, the enemy town that was taken on the third day, can easily be identified with modern Gap.  The pass which Hannibal took during the second night, can be identified with the Col de Calire. The remaining locations can be guessed at.

Day 1	March along the Drôme from to the foothills; first encounters, near Die
Night	Camp on fairly level ground; near Die
Day 2	March towards blocked Col de Cabre
Night	Attack on abandoned blockade at Col de Cabre
Day 3	Enemy attack on baggage train; capture of a fort at Saint-Mens
Night	Camp in Gap
Day 4	Easy march towards Durance and Col du Montgenèvre
Night	Camp near Prunières?
Day 5	Easy march along the Durance towards Col du Montgenèvre
Night	Camp near Embrun?
Day 6	Easy march along the Durance towards Col du Montgenèvre
Night	Camp near Mont Dauphin?
Day 7	Envoys from tribe near Briançon; ambush 10 km before Briançon
Night	Hannibal's infantry separated from cavalry and baggage train
Day 8	Hannibal's army united near Briançon; march towards Col du Mont Genèvre
Night	Camp at La Vachette, near the sources of the Durance?
Day 9	Hannibal's army reaches the Col du Montgenèvre
Night	On the summit of Col du Montgenèvre
Day 10	Halt on the summit of Col du Montgenèvre
Night	On the summit of Col du Montgenèvre
Day 11	Halt on the summit of Col du Montgenèvre; it begins to snow
Night	On the summit of Col du Montgenèvre
Day 12	Precipitous and dangerous descent for about 9 km (1854 to 1354 meters)
Night	Camp near Cesana Torinese
Day 13	Repairing the road; infantry starts to descend
Night	Elephant camp near Cesana; infantry camp near Mollières
Day 14	Building a road for the elephants; infantry descends
Night	Elephant camp near Cesana; infantry camp near Oulx
Day 15	Building a road for the elephants; infantry descends to Susa
Night	Elephant camp near Cesana; infantry camp near Susa
Day 16	Infantry stays at Susa; first of three days' rest to recover from the fatigue