The festival in Iceland that focuses on the interplay of light during the winter solstice is the Winter Lights Festival. Held in Reykjavik, this event celebrates the return of light after the dark days of winter. It features art installations, light shows, and various cultural events designed to enhance the city's natural beauty. Visitors can enjoy dance performances, concerts, and recreational activities promoting unity and joy in the community. The Winter Lights Festival emphasizes the significance of light in contrasting darkness and creates a festive, uplifting atmosphere during the longest nights of the year.