For me, the real day to celebrate the Solstice is 24 June, what the ancients called "Midsummer's Day". While the June Solstice does indeed fall on the twenty-first, the sun rises over that same spot for four consecutive days, the twenty-first through the twenty-fourth. Then, on 25 June, the sun starts moving south again and the days begin to progressively grow shorter. So many ancient tribes had their big celebration on the twenty-fourth with their festivals, midsummer bonfires, and the like. The days continue to shorten until 24 December. For the ancients, the following day was when they could see the amount of daylight lengthening again. Most of us know how that fact figures into the celebration held on 25 December.
The word "solstice" is derived from the Latin language and basically means "sun stands still". For four days--21-24 June and 21-24 December--the sun will rise over the same spot before reversing direction and moving either south or north and thus either shortening or lengthening the days. For our ancestors, marking these times was a matter of life and death as it told them how to figure their sowing, harvesting, and hunting cycles and rituals. The equinoxes were also noted, and so 20 March and 22/23 September also figured prominently in the lives of many ancient tribes and nations.
It's rather unfortunate that modern society ignores these important days and others as well. I think it is wonderful to celebrate and keep track of yearly cycles and try to attune our lives to them. I'm happy there are some of us on this board who do so. While I won't make a bonfire on Friday and dance around it, I hope to do something special to observe the occasion.
Quendi