Looks like a cave entry. But the image lacks a lot of context of what is around it, so I find it difficult to tell which one.
However there seems to be a little piece of "sky" at the left… so it would not be the cave in the crater or the boss cave in bronze door outer area. Due to this I bet it would not be the house of spirit either, or would it? And there is the text "stonebmCharacter1" which may be related to the place somehow… but still I am not getting it at the moment.
So well done
.
I will think about this during my walk in nature. Maybe a clue comes to me. I bet I am missing out of one of the existing caves. It also does not look like the ruins near Gugrontid either.