Iolani Palace - a national historic landmark and the only official state residence of royalty in the United States. The ʻIolani Palace was the royal residence of the Kalākaua Dynasty, which included King David Kalākaua and Queen Liliʻuokalani. It is located in the capitol district of downtown Honolulu in the U.S. state of Hawaiʻi. It is now a National Historic Landmark listed on the National Register of Historic Places.

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