St. John’s Day, celebrated on June 24th, is a significant feast day within the Roman Catholic Church, marking the birth of St. John the Baptist.
Never heard of this, probably because I'm not raised Christian.
The celebration of St. John’s Day predates Christianity and has roots in ancient pagan rituals that honored fertility and the summer solstice although it does not coincide exactly with the astronomical event occurring around June 20-21.
Or maybe it's something else.