The Ugly House (Ty Hyll) on the A5 between Betws-y-Coed and Capel Curig is said to be a 15th Century ty-un-nos. Under an ancient law, anyone who built a house on common land in one night, and had smoke coming out of the chimney by dawn, could claim the land around it as far as he could throw an axe. It is now the home of the Snowdonia Society, and the ground floor has been refurbished as a 19th Century cottage. There is a garden, woodlands and a nature trail.