Hjalmar Welhaven (26 December 1850 – 18 April 1922) was a Norwegian architect, palace manager, and sportsman.
Welhaven was born in Christiania as the son of writer Johan Sebastian Welhaven and Josephine Angelica Bidoluac. He married painter Margrethe Petersen Backer in 1876. His aunts were Maren Sars and writer Elisabeth Welhaven, and he was a cousin of historian Ernst Sars, biologist Georg Sars and singer Eva Nansen. He was a brother-in-law of painter Harriet Backer and pianist and composer Agathe Backer Grøndahl. He was the father of sculptor Sigri Welhaven.
Welhaven was a student at the Den kongelige tegneskole in Christiania in 1870. He later studied architecture in Hannover, and started practicing as an architect from 1875. In 1883 he was appointed manager for the Royal Palace in Oslo by King Oscar II, and he was also responsible for Prinsehytta, the Bygdøy Royal Estate and the Oscarshall castle. From 1905 he continued in this position for King Haakon VII of Norway, until he retired in 1920.
Besides his duties as a palace manager, he continued his architectural work. Among his designs were the tourist cabins Glitterheim and Gjendebu, and Polhøgda, the home of Fridtjof and Eva Nansen. He also designed several private dwellings in Oslo.
He was an eager sportsman, a member of the ski club Christiania Skiklub from its foundation in 1877, and participated in organizing the first ski jumping competition Husebyrennet in 1879. He chaired the rowing club Christiania Roklub from 1890 to 1891. His collection of skis from all over the country was shown at the 1914 Jubilee Exhibition at Frogner stadion. The collection was the basis for the ski collection at Holmenkollen Ski Museum, the world's oldest ski museum, when it opened at Frognerseteren in 1923. The museum was relocated to the Holmenkollen ski arena in 1951.
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