Because of Denmark's northern location, the length of the day with sunlight varies greatly. There are short days during the winter with sunrise coming around 9:00 am and sunset 4:30 pm, as well as long summer days with sunrise at 4:00 am and sunset at 10 pm The shortest and longest days of the year have traditionally been celebrated. The celebration for the shortest day corresponds roughly with Christmas (Danish: jul), and modern celebrations concentrate on Christmas Eve, 24 December. The celebration for the longest day is Midsummer Day, which is known in Denmark as sankthansaften (St. John's evening). Celebrations of Midsummer have taken place since pre-Christian times.