Alborg, Denmark is on the Jutland peninsula in northern part of the country, and is the fourth largest city in Denmark. It has a population of 5,364,000 and is the municipality's main city, as well as the name of a seaport. The municipality and the town have chosen to retain the traditional spelling, although the new spelling, Alborg is used in other ways, such as the Alborg Bight, the body of water. The municipality is due to change in 2007, due to the restructuring effort which is ongoing in Denmark. Aalborg is the home of the Aalborg Air Base, which is an important site for the Danish Air Force. The first mention of Aalborg has been found on a coin dated 1040, but it referred to the original name of Alabu. During the annual Carnival, 100,000 people visit Aalborg; prior to the fair, there is a "Battle of Carnival Bands," with a parade through the city--each group competes to be the leading carnival band. There are many architecture sites on the island, as well as an ancient hospital and a museum of art and antiquities.