Two islands in the Bering Strait. Lying about 2.5 mi (4 km) apart, they are separated by the U.S.-Russian boundary, which coincides with the International Date Line. The larger island, Big Diomede (Russian Ratmanov), belongs to Russia and is the site of an important weather station. To the east lies Little Diomede Island, a part of Alaska.
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The Diomede Islands (острова Диомида , ostrová Diomída), also known in Russia as Gvozdev Islands (острова Гвоздёва, ostrová Gvozdjova), consist of two rocky, tuya-type islands: the U.S. island of Little Diomede (also known as Krusenstern Island – though this may also refer to other places – or by its native name Ignaluk) and the Russian island of Big Diomede (part of Chukotka Autonomous Okrug), which is also known as Imaqliq, Inaliq, Nunarbuk or Ratmanov Island. They are located in the middle of the Bering Strait between mainland Alaska, USA and Siberia, Russia, with the Chukchi Sea to the north and the Bering Sea to the south. 15 km to the southeast is Fairway Rock, which is usually not considered part of the Diomede Islands.
The islands are separated by an international border and the International Date Line which is approximately 1 km (0.6 mi) from each island. At the closest distance between Little Diomede and Big Diomede, the two islands are only about 4 km (2.4 mi) apart. The small habitation on Little Diomede Island is centered to the west side of the island at the village of Diomede.
The Big Diomede Island is Russia's easternmost point and despite being the western one of the two islands, it is located at what is considered east on the map. In the same way, the Little Diomede Island, USA, despite of being eastern one of the two islands, is located at what is considered west on the map. The confusion between the east and the west near the 180th meridian is due to the very definition of a geographic coordinate system. For geographical and political reasons, even if located on the 169th meridian west, Big Diomede is included in what we call the eastern part of the world. Yet further east than Little Diomede, Alaska's Attu Island in the Aleutian Islands is the westernmost point of the United States even if located on the 173rd meridian east, also the westernmost point of the Earth.
In April 2007 students on Little Diomede made a QuickTime VR Panorama The QTVR files show both the US and Russian islands quite clearly, with the International Date Line tracing an invisible line on the ice between them.
The text of the 1867 treaty finalizing the sale of Alaska uses the islands to designate the boundary between the two nations: The border separates "equidistantly Krusenstern Island, or Ignaluk, from Ratmanov Island, or Nunarbuk, and heads northward infinitely until it disappears completely in the Arctic Ocean."
Because the International Date Line runs down the 4-km (2.5-mi) gap between the two islands, you can look from Alaska into "tomorrow" in Russia.
During the Cold War, that gap constituted the border between the USA and the USSR, and became known as the "Ice Curtain". In 1987, however, Lynne Cox swam from one island to the other, and was congratulated jointly by Ronald Reagan and Mikhail Gorbachev.
In summer 1995, British television actor and documentary presenter Michael Palin started his counterclockwise circumnavigation of the Pacific Rim, encompassing 18 different countries, on Little Diomede Island, as part of the BBC series Full Circle. He intended to set foot on it again at the very end of his journey lasting nearly eight months, but was unable to do so because he was returning during the following winter (on the U.S. Coast Guard Cutter Munro), and the sea became too rough to allow him and his film crew to land on the island.
Big Diomede Island was traditionally the easternmost landmass before the IDL, and the first landmass to enter new years, if using local solar time. When using official time, a large area in eastern Russia, as well as New Zealand, has the same time zone. New Zealand also has Daylight Saving time in December, but not Russia (see time in New Zealand and time in Russia). After 1995 however, parts of Kiribati count as being further east since the IDL is now going east of them, and also on a higher timezone (GMT+14).
The native population of Big Diomede Island was relocated by the Soviet government to mainland Russia and the island is currently home to a small Russian military presence. Little Diomede has an Inupiat Eskimo population of 170 , mostly in the City of Diomede. This village there has a school, and a local store. Some eskimos there are famous for their ivory carving. Mail is delivered by helicopter, weather permitting.