The constellation of Pegasus, "The Winged Horse" is one of the most easily recognizable groups in the autumn sky, and is the signpost that will enable the observer to find other, fainter groups of the season. In legend, Pegasus was born from the blood of the gorgon Medusa after she had been slain by Perseus. The horse then took the hero flying back to his homeland, where along the way, Perseus encountered Andromeda chained to a rock, awaiting her fate at the hands of Cetus. After Perseus had rescued Andromeda and returned to his home, he took Pegasus to Mount Ida, where the horse could enjoy eternity, grazing under the kindly gaze of Zeus. Pegasus was eventually placed in the sky to complete the tale of the heroic Perseus, but the winged horse itself was immortal, and tales of its exploits continue throughout Greek mythology, until finally all history of it has become lost. To the Celts this was the horse of Llyr, the sea god, a beautiful white charger that figured in many Celtic myths and still has marine associations - we call the whitecaps of the waves whitehorses. In the ancient Celtic world this constellation (and Andromeda on its back) represented the goddess Epona riding her white horse and is symbolized in the British landscape by the chalk figure of the white horse at Uffington. English tradition tells us that it was here that St George defeated the dragon; mummers plays re-enacted here in times past linked St George to the legend of Perseus and Andromeda; his white steed still stands on the hill as an effigy to this legend. Lady Godiva at Coventry also commemorates the relationship of white horses to ladies. Her ride through the city is a Christianized tale of Epona, Perseus and Andromeda and the celebration of femininity and fertility. In the Welsh folk tale The Mabinogion, Rhiannon, the bride of Pwll, Lord of Dyfed rides a magical white horse. These myths prevail even in nursery rhymes; ladies and white horses such as Banbury Cross with its association with bells and rings refers again to ancient tales of fertility and licentiousness that have sky magic woven through.