In the dawn of civilization, way before Christianity came to the Emerald Isle, Newgrange Mound was built, which on Winter Solstice, has an avenue for the sun to shine, and only on that date will it happen. Another site with this alignment might be better known, namely Stonehenge, which was built much later than Newgrange.
But Newgrange has more than the light streaming down a passageway to a particular wall only on Solstice. Remember well the skills of a culture before the working of metals, and the dedication of man-hours to erect this structure.
Wikipedia tells us: "The complex of Newgrange was originally built between c. 3200 and 3100 BC, meaning that it is approximately 5,000 years old. According to carbon-14 dates, it is about five hundred years older than the current form of Stonehenge, and the Great Pyramid of Giza in Egypt, as well as predating the Mycenaean culture of ancient Greece."
Newgrange has spirals. Inside...
And most famously outside.
Patricia Monaghan wrote in her book Red Haired Girl from the Blog, and other books like The Encyclopedia of Goddesses and Heroines, about women's spirituality in early Celtic Ireland.
And another woman, Marija Gimbutus, wrote of The Language of the Goddess, giving an archeologist's view on symbols like the spirals at Newgrange.
Just thought I'd mention how women and goddesses were probably part of early cultures that remembered the Solstices.