Aguiguan (also Aguigan and Aguihan, based on the Spanish rendition of the native name, Aguijan, which is still used) is a small bean-shaped coralline island in the Northern Mariana Islands chain in the Pacific Ocean. It is situated south-west of Tinian, from which it is separated by the Tinian Channel. Aguiguan and neighboring Tinian Island together form Tinian Municipality, one of the four main political divisions that comprise the Northern Marianas. It is likely that first sighting by Europeans occurred during the Spanish expedition of Ferdinand Magellan, or by its continuation by Gonzalo Gómez de Espinosa being charted as Santo Ángel. It was visited by the Spanish missionary Diego Luis de San Vitores in 1669. Aguiguan was administered as part of the Spanish Mariana Islands from the 16th century to 1899, when the Northern Marianas were sold by Spain to the German Empire. Under Germany, it was administered as part of German New Guinea. During World War I, Aguiguan came under the control of the Empire of Japan and was administered as part of the South Seas Mandate. During World War II, the Imperial Japanese Army maintained a garrison on Aguiguan. This garrison is noteworthy because of its surrender to Allied forces September 4, 1945, two days after the surrender of Japan. The surrender was unique as it was the only surrender hosted by a U.S. Coast Guard Cutter, the USCG 83525. US Navy Admiral Marshall R. Greer received the surrender of the Japanese Second Lieutenant Kinichi Yamada. Following World War II, Aguiguan came under the control of the United States and was administered as part of the Trust Territory of the Pacific Islands. Since 1978, the island has been part of the Commonwealth of the Northern Mariana Islands. Aguiguan is only in size, with a length of and a width of . It is nicknamed “Goat Island” due to the large number of feral goats present there. Much of the native vegetation on Aguigan has been destroyed by goats. Aguiguan is uninhabited and is seldom visited because it is surrounded by sheer steep cliffs.