Cailleach (or Cailliach) is referred to as the "Dark Mother", and the "Mother of All" in parts of Scotland. She is depicted as an old hag with the teeth of a wild bear and boar's tusks. She is said to have created the Earth. She carried a magical staff, which froze the ground with every tap.
She represents initiation through cold, hard truth. Her cauldron represents the darkness of the womb where new life pauses before coming into being.
She is associated with death and rebirth as she stands at the end of the old year and the beginning of the new. It is said that the last farmer to harvest his grain would look after Cailleach until the next harvest. The first farmer who finishes harvesting would start to make a corn-dolly from the first grain. He would then pass it on to the next farmer who finishes, and the next. It would keep going until the corn-dolly ends up with the last farmer, who would be obligated to watch the Caillach while she sleeps in her cave, then awakens as the Goddess Bride (Brighid) at Ostara. Other traditions state that she turns to stone during this time and awakens at Beltane, again as the maiden goddess.
She will show you what you need to know, even if you don't want to see it!