It's a tricky question though. The answer is not so obvious. Tintagel is a legendary castle but it was the castle in which Arthur supposedly was born and then he left it. He moved to another place and castle called Camelot so, as question states, Camelot would be _his_ castle. But there are opinions that Tintagel and Camelot were actually the same castles and Arthur never left Tintagel and the name Camelot referred to the whole area with the castle in it. There are also opinions that the Tintagel never existed and the ruins that are left are Camelot's ruins. There are opinions that Arthur wasn't born in Tintagel (but in some other unnamed place) and only after some time he moved there naming it Camelot... So as you may see, total confusion (I spent half of the day searching through internet and I'm more confused than I was before ;) But, all in all, I would stick with Camelot ;)