Changing Trains in Domodossela, ITL

Not a lot, but some.
The changes are: Zermatt - Brig - Domodossola - Locarno - Giubiasco/Bellinzona - Lugano.
The change at Domodossola involves going to the underground part of the station, but not significantly more steps as may be involved changing platforms at the other stations.

Edit: It's "stains", I misread. No stains unless you fall over in the mud ☺

jim,

The rail trip that Chris described will take about 5.5 hours with 4 changes. You'll be using the FART Cento Valli railway from Domodossola to Locarno, and the stations are underground at both ends. It's a very scenic trip! I don't recall there being a lot of stairs in Domodossola. Once you're down at the platforms, you'll have a level walking surface. Once you arrive at Locarno, hopefully the Escalators are still in operation. At Locarno you'll have to go up to street level and walk to the "other" rail station, which is next to the FART station as I recall.

I take it that the train from Brig comes in at street level in Demodossola?

Maybe Ken can shed more light on this. The main line platforms at Domodossola station are indeed at street level, but often you do have to use the underground passageway to get from the "island" platforms to the main station. That is the only way to get across the tracks, so you go down a stairway to the passageway, walk to either the main station or other Island platforms, then up a stairway to get there. This is almost universal at train stations throughout Europe. The only exceptions are at big city terminal type stations where all the platforms come to a head and you can walk between them at one level.

I have never transferred to the FART at this station, so I don't know if there is a way to the FART platforms from the underground passageway without going up the stairs to the main station.
Here is a photo of the entrance to the FART platforms from the street outside Domodossola station. Looks like there could be an elevator, but when I zoom in, the signage is not readable.
https://www.google.com/maps/@46.1150307,8.2961367,3a,30y,86.93h,85.04t/data=!3m6!1e1!3m4!1sVMNEWMwBqPPG-M62W-kp9w!2e0!7i13312!8i6656

I've done that change but it was a few years ago so memory may not be firing on all 12 cylinders. I don't remember any alternative to stairs at the FART. I do remember snaking lines as everybody tried to get on and off the little FART train in a narrow area. I don't remember any excessive walking.

"I have never transferred to the FART at this station, so I don't know if there is a way to the FART platforms from the underground passageway without going up the stairs to the main station."

My memory is also a bit foggy on the subject of access to the FART station in Domodossola. However I don't remember any access to the main station from the Sottopassaggi in the main rail station. The FART station seemed to be self-contained, with the only access being the stairway. Given the increasing emphasis on "accessibility" these days, I wouldn't be surprised if there's now an elevator. Perhaps Jim can let us know after his trip.

I just did this route in mid-October 2018! There are lifts from ground level down to the FART stations in both Domodossola and Locarno. The lift in Locarno down to the FART stations is just right behind the escalator entrance, and that is a very short walk from the SBB platforms. In Domodossola, the Brig train comes in at ground level. There are well marked directions to get from the mainline train platform to the underground FART station, which can be accessed by both a stairs and a lift. The signage reads "Valle Vigezzo Centrovalli Locarno". Try doing a Google Map search for "Domodossola - Stazione" and using Browze Street View images click on the little blue dot on top of the pink train track to the right of the station location on the map to see a picture of the platform showing both the stairs and the lift. I don't recall that the walk to the FART station was very long.