A snow lantern is a hollow cone built of snowballs into which a light is put, usually a candle or a Japanese stone garden lantern Yukimi Gata.
[1] People lighting their own snow lanterns is one of Sweden's, Finland's and Norway's Christmas traditions.
[2] Hirosaki in Aomori Prefecture, Japan holds an annual winter four-day Hirosaki Castle Snow Lantern festival at Hirosaki Castle.
The festival had attracted 310,000 visitors in 1999 and included 165 standing snow lanterns and 300 mini snow caves.
[3]