My questions probably stem from repeated viewings of the HBO series ROME.
How long did it take to march an army from Rome to Gaul?
What was the average travel time by ship from Rome to Egypt & Greece?
Please share any ancient travel tidbits.
In the spring of 218 BC, Hannibal started his famous journey from Carthágo Nova (now Cartagena) in the south-east of Spain with the intention of invading Italy. The march from Cartagena to the Po valley was, and probably still is, a distance of about 1,000 miles. Beginning with an army of approximately 90,000 infantry, 12,000 cavalry, and 37 elephants, it took him about five months, although by no means all his forces survived the trip.
Hannibal arrived at Avignon with about 290 miles remaining before reaching his destination of the Po valley. The army travelled 160 miles north alongside the river RhĂ´ne in 16 days, before crossing the Alps, a further distance of 130 miles, in 17 days, making the total time taken for this section of the route 33 days.
(The Avignon - Po Valley route, the distances for which are given in English miles rather than Roman miles, was travelled by the Greek historian Polybius, the author of an account of Hannibal’s passage through the Alps.)
From the Po valley at the foot of the Alps to Florence is about another 30 miles, and Florence is 143 miles from Rome. If Hannibal had continued to Rome it would have taken him about another 17 days.
Therefore, in 218 BC, a march from Gaul to Rome across the Alps, with infantry, cavalry, and elephants, would have taken approximately 50 days.
Main source: Hannibal crosses the Alps by Cecil Torr, citing Polybius.
It depends partly on the terrain, and partly on whether you have good roads. Hannibal was going over mountains, and without good roads, so it took him longer than t ould for the Romans after they built the roads. (And that’s why the Romans built them). On a good road, marching, an army can travel at least 30 miles a day, and more if they are in a hurry.
The OP is asking about Rome to Gaul, a trip which must be travelled over mountains. Also, regarding the condition of the roads, that’s the reason I chose to be specific about the date and the circumstances.
However, it’s maybe worth noting that, according to the U.S. Dept of Army, Staff Officers’ Field Manual: Organization, Technical, and Logistical Data, Part I (1961 and 1971):
30 miles a day is 10 miles a day over and above a minimum forced march in today’s terms, and a forced march rate of progress up a mountain must be a difficult pace to maintain, even for a Roman army.
Furthermore, from the same source:
Of course, this detail fails to include road conditions.
Link.
On the question of ship travel:
From Puteoli (now Pozzuoli - see location on map) to Alexandria (northern Egypt) by sea is a distance of 1,000 miles and the journey took 9 days.
The distance by sea from Puteoli to Corinth (Greece - see location on map) is 670 miles and the journey took 4.5 days.
The duration of both trips is given as the time taken under favourable circumstances.
From your own cite and from other you must know that Hannibal was fighting native tribes for most of his passage. His army had to stop and fight, and make several detours. They also avoided a Roman force sent to intercept them by making a large detour. They trail blazed much of their journey - following streams and climbing passes. They had to scout the route ahead include finding a feasible passage over mountains, forage along the way for food, clear obstacles for carts and elephants. The journey was remarkable - but not useful for judging how long it would take the Romans to travel down a maintained roadway (mountainous or not) that could readily provide help and provisions to marching soldiers.
While ten miles a day is rather low, it’s not even remotely unusual for an army. Army speeds tend to range from about 20-30 miles a day. Fifty is about the upper limit, and that would be a well-disciplined Roman army over good roads. A very well-motivated but small body of light troops moving over even terrain around the clock can do much better, but that’ll exhaust most people very quickly.
I can try and look up sea travel later.
As Chez G. indicates, an average speed around 4 to 5 knots (100 to 120 nautical miles a day) is a reasonable assumption given decent weather. Adverse winds could play havoc with this.