Raw ore wasn't the limiting factor for iron production: it was all about the wood. Coal has the issues that, without coking, it neither burns hot enough nor clean enough (i.e. it adds lots of sulfur to the iron, and the resulting alloy is inferior for pretty much all purposes). As a result, iron and steel production wasn't as bound by locality to mines nearly as much as it was by locality to fuel sources (i.e. forests).
To give a sense for the figures involved, 1kg of iron would require around 15kg of charcoal, which itself would have to be charcoaled from >100kg of wood.
From this, you end up seeing things like Elba being entirely deforested by the time of Caesar, and its still productive iron mines would have their ores shipped to the mainland for processing.
That’s not the complete picture. If 2-5 kg of iron ore + 15kg of charcoal makes 1kg of iron then moving the iron ore to charcoal is more efficient than moving charcoal to iron ore. The same was true of coal, though coal trade was extremely common for it’s use in heating and cooking.
Anyway, Bituminous coal was used in smelting of iron ore in Roman Britain, and China had long been using coal for steel production by that time period.
Also, wood was very much an abundant but managed commodity with various levels utility. Land was reserved for effectively farming it even after forests disappeared. The issue was these managed forests weren’t producing giant long straight trunks that you would find in old growth forests. Wood that’s fine for cooking or matching charcoal, can be useless for shipbuilding.
But that means you'd need to be constantly building new smelting facilities as local wood resources were used up. Making charcoal needs relatively little infrastructure, so it'd be easier to make and transport.
I suspect the optimal answer is a combination of approaches. Build a few foundries distributed optimally near large forests, cut timber and char it and bring the charcoal to the foundries. Maybe cycle them on a 40 year basis so you can re-seed the forests and grow enough timber to make them worth it.
This is one reason why Minnesota's large iron ore deposits were concentrated locally (if necessary, some of the Mesabi Range ore is already 65% iron) and shipped to Pittsburgh (near coal mines) for steel making, instead of shipping the coal to Duluth.
I grew up somewhat near railroad tracks in Minnesota, and it was surprisingly late that I realized most train tracks aren't littered with taconite pellets that fall off during transport.
To give a sense for the figures involved, 1kg of iron would require around 15kg of charcoal, which itself would have to be charcoaled from >100kg of wood.
From this, you end up seeing things like Elba being entirely deforested by the time of Caesar, and its still productive iron mines would have their ores shipped to the mainland for processing.