Yes the original version and the one to be shown first on S4C and S4C on BBC iPlayer was in Welsh.
I have watched the two series in Welsh. I can't speak Welsh but it is a language I would like to learn and have a bit of vocabulary but it was easy to follow with subtitles.
Thanks for identifying that second garage as being in the south.
Personally though it has been made by the same production team I don't think Craith / Hidden has been quite as good as the previous Police series Y Gwyllt / Hinterland.
That had the edge and I liked the way the back story built up over three series over their creepy boss Superintendent Prosser. I always knew they would end up arresting him in the end.
The location photography was absolutely spot on around Ceredigion - Aberystwyth / Borth etc featured heavily. One episode was pretty good for railway enthusiasts as it centred around Borth Station and the station Museum.
Some of the rural locations were full of atmosphere I wonder if someone in the production crew was a bit of an urban explorer?
To be honest I would like to see a fourth series of Hinterland more than a third series of Craith.
John