Dun Darach is an arcade adventure published in 1985 by Gargoyle Games for the ZX Spectrum and Amstrad CPC computers.
The background history is based on Celtic folklore about the hero Cuchulainn, and his battles against the people of Connachta in ancient Ireland. "Dun Darach" or "Dún na nDarach" means "Oak Fort" in the Irish language. The game is a prequel to the 1984 game Tir Na Nog as the story takes place before that game, when Cuchulainn was still alive.