The Twrch Trwyth is a legendary monster boar who is especially connected with the story of Culhwch and Olwen. This medieval story, which forms part of a collection of legends known as the Mabinogion, tells of a young squire, Culhwch, who has to perform a series of impossible tasks in order to impress Ysbaddaden Bencawr, the evil giant father of Culhwch’s beloved Olwen.
The biggest and hardest task is to recover the magical comb, razor and scissors, which are entangled in the mane of the Twrch Trwyth, and bring them back to Ysbaddaden (so that he can shave his beard for the wedding!).
Culhwch asks for the help of King Arthur and his warriors and they set off to Ireland to hunt the Twrch Trwyth. Things all go a bit wrong however, as their ambush enrages the Twrch Trwyth, who sets off with a posse of his monstrous boar family, across the sea to Britain, leaving Culhwch and company stranded in Ireland. When they eventually get back to Wales, they see that the Twrch Trwyth’s revenge has been swift and devastating, having ravaged towns, villages and crops across the country.
The band of warriors eventually catch up with the Twrch Trwyth, and one by one, the horrific boars are killed, but the Twrch Trwyth is too strong. Finally, King Arthur and the Twrch Trwyth do battle on a cliff top and end up falling into the sea, with Arthur managing to wrestle the vital beard-grooming kit from the beast. Arthur gets back to shore, but watches as the invincible monster boar swims back across the seas to Ireland, having left a path of carnage and destruction behind him.