I think Mary Stewart is the author of the “Merlin-based” Arthurian stories you were trying to remember. She wrote 4 books on it, beginning with “The Crystal Cave”. She’s one of my fave writers.
“I think Mary Stewart is the author of the “Merlin-based” Arthurian stories you were trying to remember.”
Yes! Mary Stewart! I loved those books. I still have the whole set in my library somewhere but couldn’t find them to verify it. Thank you.