This is the short route I found from the Ligurian coast to the southern upper Po Valley. The Romans might have markedly less costly overland routes over the Apennines at the southern end or through some pass in the middle, I did not investigate that range. This is by far the lowest Alpine pass (being in fact deemed the transition between Alpine and Apennine ranges) and I note no modern roads of any distinction run through it. Nowadays Genova is the favored port, in fact is Italy's largest port, and developed roads run more or less straight north from there. And by the early 2nd century CE there was a major Roman road running that way too, although I have no idea how suitable it was for wheeled traffic of any kind--the Romans built roads with legions on the march in mind, and in the Alps (OTL) made roads running up to 20 degrees slope--whereas modern auto/truck ("lorry" in Commonwealth-talk) routes try to avoid going higher than 5 degrees. Railroads of course need still lower slopes. Genua was politically favored by the Romans as an ally while the modern small coastal towns you can find on this map were, according to Wikipedia, anciently of greater note-but they allied with Carthage and paid the price. It looks to me like trade from the Ligurian coast to the valley was of minor importance--that the rival coastal towns favored by Etruscans and Greek traders, though greater than Genua, were still of very little significance and probably existed mainly to serve the coastal region itself, with over-hill trade very peripheral to anyone's concerns.
And yet, unless I have failed to stumble across some hidden advantage of a longer and higher route through the western Alpine passes (where Rome later put two major and a few more secondary transAlpine roads) these would be the least bad choices for Massaliote based traders by far! Whereas the Romans can easily reach the east coast and the Po mouth itself by sea in the Adriatic, and trade up the river, and the produce of the relatively rich valley is of interest to them via Adriatic routes. They can also more easily use the produce of the valley and have more urgent and immediate need of it, and the possibility of going northeast to Istria and perhaps beyond toward the Danube is of greater marginal use to them than the League that already has wide prospects of gradually moving into La Tenê Celtic territories; the central European arm of that vast culture group is presumably more backward and rustic than northern Gaul, so what is the point of going that way? OTL the Romans took a long time to develop the Danube regions and then lost control of them early. Roman ambition would probably not aim that way--but anyway it makes more sense for them to do it than the League to look ahead and want to.
Below is an edited version of the post I was working on with regard to the basic geography:
...
...Epirus/Illyria/...
- The involvement of Epirus in Illyria leads to strengthen the relations between Epirus and the Aetolian League ( a semi independent vassal of Epirus), which approve the suppression of Illyrian piracy. This was a crucial move that help Alexander II to stabilise his realm....
Rome
- The roman army under consul Centumalus won a major battle against the Samnite army near Asculum. The Samnite king Gavius Egnatius, desperate by this loss asked for help from the Megale Hellas League(an unofficial ally). The Greeks fearing of Roman aggression decide to help Gavius Egnatius.
Well well! I'd pretty much written off Epirus as a one-reign wonder, due to Pyrrhus's unique genius, and that Alex II had demonstrated incompetence foreshadowing the collapse of the whole thing. Epirus itself strikes me as economically only marginally better off than wild Illyria, rough hardscrabble land mainly good for producing tough warriors--but in modest numbers. Led by a military genius they have the potential to run roughshod over wide territories, but it takes a political genius to stabilize such a regime. Not knowing how good a job Pyrrhus did in southern Italy I gave him benefit of the doubt and figured maybe his heir learned a thing or two at his father's side; the quick loss of control of wide regions that followed the elder's death in battle, and the crude draconian solution A II came up with suggested to me the day of the Epirote reign had come and gone.
Now perhaps we see that the kid just had some learning to do, and it is too early to count the kingdom out. With the south Italians calling on him and the League for help again, we might see a second triple alliance war.
But that merely underscores my opinion the solution between the League and Rome will not be a peaceful one. The situation has some potential for that--if the League has enough influence over the course of another war (which must mean it is less peripherally involved in the Italian campaign) it is possible, if Massaliote leadership is visionary enough, that they might offer a statesmanlike truce meant to last.
However that means once again attributing to the League insights and perspectives that are rather anachronistic. This era is not one of Westphalian style states and hence not Westphalian statesmanship. Such things would have to be precociously invented, it would take acceptance of a new sort of understanding of politics on all sides, not just one, to spread them. OTL of course the Westphalian era began as a settlement of the destructive stalemates of the Thirty Years War, whose parties entered into it with much more sweeping and absolutist goals then they left it off with, and only after massive devastation with catastrophic results. For some visionary to conceive it in advance of such compelling lessons, and for the Romans to accept it...would need a whole lot of explaining and most likely is simply unreasonable.
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I've had a closer look at the geography of the western Alps that separate Massalia's core region from the Po Valley. I suggest everyone do the same. The situation is rather worse than I thought. It is not so much the height of the Alpine passes that bother me, as the breadth of the highlands leading up to them. In that terrain, we can expect that all the tributaries to the Saone-Rhone system the queen city of the League presides over very quickly reach heights and slopes where rapids and a shallow, fast-flowing stream completely unsuited to water transport of any kind. Beyond this point on the various streams, which I expect form a contour of an effective fall line, all trade eastward is going to be conducted over land. And it is terrible country for roads too! Solutions along those lines may exist. The Romans of course have the retrospective reputation of being the civil engineers
par excellance of the Classical world, particularly in the matter of road building, but I'm not sure how they handled the task of mountain roads. Anyone who knows a lot about that, and in particular what solutions they adopted in connecting Cisalpine to Transalpine Gaul, has got something very valuable to contribute!
I reasoned that actually the mountain barrier is thinnest on the Ligurian coast, the westernmost stretch of modern Italy connecting to the
Cote d'Azur of France. And indeed in looking at lists of Alpine passes, the one that actually is taken to define the border between the ridge of the Apennines and the Alps proper.
This map
shows many features of interest to this discussion, such as the specific peoples involved in coming to some sort of settlement of the Cisalpine question. I show this one in the post, rather than the even more detailed terrain map linked below, because if we are going to discuss the fate of regional powers messing around in the valley we probably need to pay attention to the particular peoples living there. The map implies a relative few big communities of native peoples--and underplays how "Gaulish" they are, because a lot of the peoples shown who aren't shown as Gauls have been strongly influenced by the Gaulish neighbors and might well be regarded as outsiders as sort of Gaulish themselves. I was under the impression the actual political picture is a lot more fragmented, and I suspect it actually is, with what appear to be unified tribes actually subdivided into tens of little kingdoms, along the lines of Ireland or Britain. But I gather that very little is actually known, and what is written was written mostly by their Roman and other enemies, so there is ample room for speculation I guess. An expert judgement would be nice!
But for now, I'm just looking at the broad geography of the situation.
On this map it would seem that due south of where the letter "R" in the name of the Ligures people appears there is a gap, and indeed on t
his bigger map of the Alps around Italy this seems to be borne out. However, when I looked up that lowest point,
Colle di Cadibona, although its height of 436 meters is far lower than the other major passes which often exceed a kilometer in altitude, its location does not appear to be a major link between the upper Po valley and the Mediterranean. Rather that honor appears, judging by modern roadways, to go to Genoa. Indeed looking at
this map of the Empire and its roads (big file, but useful to have!) it seems they did build a straight road running north from Genua into the valley. Thus the easy road from Rome to Gaul, I would judge, would be coastwise long the north Apennine shore, and from Cisalpine Gaul to larger Gaul, south on that road to Genua and thence west. The map shows two other roads penetrating the Alps into Gaul in the northwest, but I imagine these were not as favored for trade though I daresay they did provide the fastest communications.
Here's another map showing more local roads, and we can see a couple other routes into Gaul, but they branch off the larger main roads.
You see, men on foot, and horses, and still more donkeys or mules, can tread on paths that wheeled vehicles cannot negotiate. Roman roads were all originally laid out with the needs of legions in mind, and only later did the Romans deviate more than they absolutely had to from their practice of running them straight as possible, up and down slopes rather than meandering around to trade off gradient for longer routes. Thus I would expect none of these roads to be convenient for wheeled vehicles.
Anyway, reading up a bit on the history of Genoa it appeared that city was originally overshadowed by Vada Sabatia (today named Vado Liguria) and Savona, and indeed these towns are near the pass of Cadibona. The Roman major roads don't go that way nor do major modern ones, but the secondary roads on the unlabeled map seem to come close. It appears that the Savones tribe allied with Hannibal in the Punic wars whereas the Genuans were Roman allies--leading to the latter town being razed during the wars but then favored for rebuilding afterwards, and I suppose the Romans built the road northward to help nail down the supremacy of the favored city. Even so, neither Genoa nor the eclipsed former Slavonian towns amounted to much in the Dark Ages, so I assume modern Genoa's prominence as Italy's premier port is partially a function of the city developing extensive trade in the Middle Ages and later, partially a legacy of Roman engineering suitable inland connections, partially due to the rise of Northern Italy as the center of Italian industry and the desirability of the modern Po Valley communicating with the Mediterranean without the roundabout route via the Adriatic, and thus modern road engineering has also come into play.
Thus it is not clear to me whether the Genoan route is naturally superior to that which could be blazed north from Savonia. I have attempted to find that route using a Google maps walking route; the northern terminus is beyond the pass of Cadibona, I don't know why the Google map search chose it. {I'm referring again to the image at the top of the post} The route is listed as being some 101 km and estimates over 22 hours of walking time. I figure a legion on the march would take a couple days to traverse it but it is possible a Roman road would cut a fair distance out by taking steeper shortcuts--Alpine Roman roads went up to 20 degree slopes, whereas a modern automotive superhighway such as say US Interstate 80 through the Donner Pass from Sacramento to Reno tries to avoid slopes as high as 5 degrees. Human feet, or those of donkeys or carefully paced horses, can pick out considerably steeper slopes. Of course the Romans did want their baggage trains to go over the roads too. I would think then such a route might be passable, but slow, for carts being pulled by sufficiently large teams.
I have been writing more about my reasons for doubting a lasting peace can be made between Rome and the League, mainly because of Roman mentality and a reasonable observation that Rome, even if it ultimately holds all of Italy, is probably not strong enough to strike east without having a lot more territory in hand first, and that it is hardly in Massaliote interest to have Rome attempt to take the place of Ptolemaic Egypt. I might post something based on that but I'll try to avoid merely repeating these claims of mine unless there is some useful expansion that can better carry the point.
I think this geography lesson is enough to explain why I think Massalia has little leverage in the Cisalpine situation, and is doomed to face an aggressive Rome that does hold the region against them. For alternatives to Rome inevitably getting it, or as a belated remedy, more likely than the League expanding east to possess the Po Valley, would be bringing in Epirus again to finish the job Pyrrhus left undone, and take and reduce Rome once and for all--for a time, the Balkan power would have to digest Italy, but eventually, after some generations, a lasting Epirote regime in north Italy (and probably including the south as well) might pose exactly the same sort of threat to Massalia again. Perhaps by then the League will have gained so much strength it would not seem politic for even a mighty Epirus ruling the entirety of both Italy and the Balkans including all of homeland Hellas to try it. But while the League seems to lead a charmed life, we ought to expect it to come on hard times sooner or later--a strong Italian power might seize that moment to close in for the kill.
OTL since the Romans, no one has done this to my knowledge--that is expand from a strongly held north Italy to seize the southern French coastline. It has more often gone the other way. But probably not as an economically profitable venture!
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sorry for any other mistakes!
