Trading in Bergen may have started as early as the 1020s. According to tradition, the city was founded in 1070 by king Olav Kyrre; its name was Bjørgvin, "the green meadow among the mountains". It served as Norway's capital in the 13th century, and from the end of the 13th century became a bureau city of the Hanseatic League. Until 1789, Bergen enjoyed exclusive rights to mediate trade between Northern Norway and abroad and it was the largest city in Norway until the 1830s when it was surpassed by the capital, Oslo. What remains of the quays, Bryggen, is a World Heritage Site. The city was hit by numerous fires over the years. The "Bergen School of Meteorology" was developed at the Geophysical Institute beginning in 1917, the Norwegian School of Economics was founded in 1936, and the University of Bergen in 1946. From 1831 to 1972, Bergen was its own county. In 1972 the municipality absorbed four surrounding municipalities and became a part of Hordaland county.