Hankø Island is located in the Oslo Fjord, Østfold county, Norway. It used to be the property of the Dano-Norwegian king, the site where the king hunted deer. Later an island of retreat, notable visitors are the Norwegian king, Princess Märtha Louise of Norway,and her husband Ari Behn. Their second child, Leah Isadora Behn was born at their estate "Bloksberg" in 2005