Here's a charming article about Ivana Kupala, a Ukrainian holiday celebrated with bonfires and flower wreaths, after the summer solstice, usually on the night of July 6.
The name Kupala refers to the god of fruits of the earth. His holiday is considered to be one of the most magical ones in the Ukrainian calendar. Fortune-telling, jumping over cleansing fires and other mystical rituals have traditionally been part of it. . . . Olena Didiuk, who had done a bachelor degree paper on pagan holidays assimilated by the Christian tradition, explained how the name Ivan merged with the holiday. “Christianity was brought on the Ukrainian land against the will of pagan people, and the church needed to set new holidays on top of the old ones. So today people have a choice whether to celebrate Ivan the Baptist’s day, or the day of Kupala,” she said.
Picture from the article; there are several really lovely ones.