Gweyr is a random encounter in the northern-most zone, I generally encounter here on the four-across horizontal line of squares in the middle. There is an ice tower at the very north of the Glacial Rift, but if you instead mean the fire temple where Brienne learns her new set that's actually in the ice forest(?) between the Wayfort and Winter City. From the Wayfort exit, turn right then head up to find the fire temple.
Nope, the Temple of Terrestrial Fire is in the Frostwood. It got signposted way before it appeared, at least if you have Ryn in your party at the time you step on the tile.
Oh, and Gweyr only appears after completing Harboring a Fugitive so if you're on a run where you haven't completed that yet, it's probably why she's not appearing.
Oh, and Gweyr only appears after completing Harboring a Fugitive so if you're on a run where you haven't completed that yet, it's probably why she's not appearing.
Ah, that would explain things. I haven't done the quest yet because the way to do it right is not on the wiki yet.