Colour photo of the hut yesterday. It is in fact a fisherman's hut and has been there as long as I can remember. The season for lave net fishing for salmon in the River Severn used to start in February. This type of fishing involves standing in the river as the tides runs out so they needed somewhere close to store their nets, sometimes a small boat and their waders and equipment. I'm sure it was very welcome to be inside after getting cold. The river is the other side of the bank and the hills are on the other side of the river.
The hut still looks quite solid and may be used. We have the same sort of huts but much smaller for white baiting on the rivers! Makes a great scene looking out over the countryside!