This year's solsitice is on 21st December at approx 3pm, of course the actual time is the same every year by the sidereal calendar, but by our modern Gregorian calendar, introduced in 1585, it changes slightly, every year.
In Ireland the most famous Winter Solstice site is of course Newgrange, part of the Brú na Bóinne complex of 3 sites. Newgrange itself is called Sí an Bhrú or its older name of Síd in Broga. The pillar-box light shaft, once filled with 2 quartz stones, famously allows the illumination of the stones in the rear of the passageway, on the solstice. The word in Irish, grianstad, translates as 'sun standing' or rather 'sun standing still', which is because for approximately 3 days the minimal height of the risen sun remains constant, before it starts to slowly ascend again. The latin based word solstice has a similar meaning - 'sun stopped', but of course the sun never actually stops or stands still, it is just an illusion from the perspective of humans standing here on Earth.
Newgrange is the 'classic' Winter Solstice site, being aligned to the sunrise, and only about 12/13 km from the east coast of Ireland, on high ground, with nothing significant to block the view, although the sea is not visible from Newgrange. What is less well-known are the other sites aligned to the solstice (or both solstices) around Ireland and in particular those aligned to the western sunset on the Winter Solstice.
From the west coast, the sunrise is later by 10 or so minutes and often less spectacular. What we do know is that there are megalithic sites on or near the west coast of Ireland, of similar age to the Brú na Bóinne monuments, that are aligned to the Winter Solstice sunset. One site of note is the Ardmore (Arda Mór) Stones, on the Dingle Peninsula, which consists of 3 large menhirs in a straight line and a 4th stone at a right-angle to the alignment. The 3 main stones are illuminated by the setting sun, assuming good visibility, on the Winter Solstice, an event that is still marked by locals (and visitors) who attend the site even today, although in tiny numbers compared to the fanfare surrounding Newgrange.
This is just one of many sites aligned to one or both solstices, which shows that Newgrange is not the only place that was importance at this time. In ancient Ireland travel was more difficult than today, so it makes sense that localized gatherings would have been common, to celebrate this and other significant celestial events.
https://www.megalithicireland.com/Ardamore%20%20Stone%20Row,%20Kerry.html
