Perhaps surprisingly, given that we might fairly expect that the area we would be travelling through would be the least 'modern' of our trip, this turned out to be the easiest stage of the tour to date.
After spending an hour or two in Foix itself - including a raid for picnic fodder at a small supermarket - we headed for the station, concerned a little to make sure that we could get our bags into decent spaces and find ourselves the best seats possible, since this was to be a two-hour jaunt.
We had no such worries - although the French do seem to like taking as much space as possible on a train, and we had to settle for a pair of seats facing the way we'd come.
Within a few minutes, as we started a noticeable climb out of Foix, I was in danger of getting a crick in my neck. So we were quite relieved, just two short stops later, when enough people departed to leave us a pick of seats, with a big window and the chance to sit back and appreciate the scenery more fully.
And it was worth appreciating, as we moved higher and higher. The architecture was fascinating: a combination of the Alpine and the brightly coloured walls and shutters of Pays Catalan.
We ran alongside the still fast-flowing Ariege, moving nearer and nearer to it's source, marvelling at how clear it looked, musing on how it would be to scoop up a handful and drink.
More gravel industry was visible, together with what seemed to be regular power stations by the running water.
There was a semi-constant sense of 'ohhh' and 'ahhh' as we rounded bends to see spectacular new panoramas laid out before us. The heavily wooded mountains eventually showed signs of a tree line, but the charming upland meadow alongside the tracks remained.
Out of the corner of your eye, you'd glance butterflies fluttering away, while beehives lay dotted around; sometimes singly, sometimes in large groups.
The trip took us within a stone's throw of Andorra and left us, a short while later, at La Tour de Carol, a vast but almost deserted station that is effectively a border halt for France and Spain.
But with Schengen rendering passport checks between the countries a thing of the past, it is a very quiet place that has seen better days.
The platforms were low though, so as had no trouble getting out of the train, and even had the novel experience of having to walk across the tracks to the station building itself.
With mountains all around and the odd, lazy lizard sunning itself, there was something sleepy about the place, as vast old sheds and buildings decayed slowly in the languid atmosphere.
Le Train Jaune, which travels by narrow gauge to Villefranche, pulled in soon after. But like everything about this part of the journey, it was going nowhere fast.
The solitary station shop was shut until the early evening and no sign existed of food and drink. We were glad for the little picnic.
We had a break of 90 minutes between trains. For me, a wander around the old station with the camera, unobstructed, had its fascinations, and that was followed by time spent writing, iPad propped up on my case.
And so, with a few other travellers and a couple of dogs, we waited.