Also known as Gwenfrewy or Winefred. A beautiful and pious young noblewoman who was murdered by an amorous swain after she spurned his advances. The would-be lover struck off her head with his sword; a healing well (Holywell in Flintshire) is said to have sprung up on the spot. Fortunately, her uncle, Saint Beuno, was preaching nearby, and was able to bring her back to life. Later, she became the abbess of a group of holy women in Gwytherin, Wales.
Images of Saint Winifred's Well can be seen here can be seen here on the Castle Wales website.
O Winifred, our glorious lady,
Calm for us the billows of the sea,
Lest we become the ready prey of the enemy,
O compassionate one, afford us thy protection.
- from the Complete Old Sarum Rite Missal (read the whole prayer here)
The Golden Legend relates an expanded story of the Life of Saint Winifred.
And if you are traveling in Snowdonia, check out "Winifred's Rest" Bed and Breakfast in Trefriw. It sounds like a nice place to stay.
One of the items on the breakfast table is BARA BRITH, a hearty Welsh fruit bread, with the unique ingredient of fresh brewed tea - the fruit soaks in it, and the liquid is added to the dough. Britain Express website has four recipes for it (one uses coffee instead of tea) and the directions look easy enough. Epicurious has another recipe that includes orange marmalade.
Then settle back and read "A Morbid Taste for Bones" by Ellis Peters, in which the bones of Saint Winifred become a matter for murder between the people of Gwytherin and the monks of Shrewsbury Abbey.