Question: What former naval base was captured by the son of Angus MacDonald? 
Sentence (from "Dunyvaig Castle"): Dunyvaig Castle, (Scottish Gaelic: "Dùn Naomhaig" , Anglicised "Fort of the galleys", also known as "Dunnyveg") is located on the south side of Islay, in Argyll, Scotland, on the shore of Lagavulin Bay, 4 km from Port Ellen.
Relevant evidence: Yes