Does anyone remember this children`s fantasy book?

Question

I read it back in school during the 1980`s.It concerned a semi-devine hero who had one golden arm and his companion who was a "twice-born" something that rendered him immortal.All I can remember is that it featured stonehenge and seemed to have it`s inspitaion in British and Irish Celtic myth as well as the Norse sagas.

Answer 1

The book I am thinking of is by Guy Gaverial Kay, and it's actually 3 books. They're titled 'The Summer Tree', 'The Wandering Fire', and 'The Darkest Road'. They make up 'The Finovar Trilogy'. Most of the story is taken from the Celtic myths. It starts in Canada with 5 college students who go to see a Celtic speaker on campus. They find out the the speaker is actually a mage from Finovar. He takes them back to Finovar where they meet the king, one of his sons, and assorted other folk. One of the visitors becomes Pwyll Twiceborn, he goes to the Summer Tree as a surragate to the old king. The goddess sends him back. That's why he is called "Twiceborn". Hope this helps and this is the book(s) you are looking for. However, they aren't children's books.