International trips made by the heads of state and heads of government to the United States have become a valuable part of American diplomacy and international relations since such trips were first made in the mid-19th century. They are complicated undertakings that often require months of planning along with a great deal of coordination and communication. The first international visit to the United States was made by King Kalakaua of Hawaii in 1874, which was the first visit by a foreign chief of state or head of government.