Llyn Lliwan

---

A marvelous lake along the river Severn in Wales, which filled and emptied according to the tides.

During the hunt of Twrch Trwyth and its piglets, a magical leash was used to capture one of the piglets.

---

Source
Historia Regum Britanniae | Geoffrey of Monmouth, c. 1138
Culhwch and Olwen | Late 11th century