Big Diomede, Russia

Big Diomede or Ratmanov Island (Chuk. Imelin, Inuit. Imaqliq) is an island in the Diomede Islands in the Bering Strait, the most eastern point of the territory of the Russian Federation.

Administratively it belongs to the Chukotka region of the Chukotka Autonomous Okrug. There is no permanent population on the island; the base of the Russian border guards is located here.

Named after the Russian navigator M.I.Ratmanov.



The highest point is Mount Krysha/ Roof, 505 meters. It is located slightly south of the geographical center of the island.

Depths off the coast reach 43 meters.

The coast is rocky, in boulders, with a narrow strip of coastal beach, only the northern coast is relatively gentle. There is also a polar station. There are several rivers, two of them flow from the center of the island to the north, one flows from the top of Mount Krysha  to the southeast. The length of the island from north to south is 8.7 km, from east to west - 4.7 km. From Big Diomede Island to the Chukotka coast 35.68 km. The extreme northern point of the island is Cape Horseman, east of which is Cape Skalisty. The southernmost point of the island is Cape Yuzhny.

In line of sight from the island, there is a smaller island, Krusenstern Island, owned by the United States.

In the center of the strait between the islands is the state sea border of Russia and the United States, which was formed after the sale of Alaska. The date change line runs along this strait: the day begins on the Ratmanov island, and ends on the Kruzenshtern island.

The infrastructure of the island is relatively developed, there is a polar station, a border post and many different buildings on the coast and south of the center of the island.


Historical background

The island was first visited by the Europeans by the expedition of Semyon Dezhnev, about which there is a written report dated April 15, 1655.

In the summer of 1728, Vitus Bering approached the island, who gave it the name Big Diomede - in honor of the saint, on whose day, August 16, the expedition arrived at the island. Four years later, I. Fedorov and M. S. Gvozdev, it was mapped. Prior to this, the local Eskimos called the island Imaklik (Chukot. Adap. Imelin) - “surrounded by the sea”. There were two settlements here - Kunga and Imaklik with a population of approx. 400 people.

In 1816, the Russian polar explorer Otto Kotzebue, while exploring the Bering Strait, mistakenly discovered another island in the archipelago of the three Diomede Islands, which he named after his colleague, officer Makar Ratmanov, a member of a previous naval expedition. When a mistake was discovered, the name was transferred to one of the islands of the Diomede archipelago.

On March 30, 1867, the sale of Alaska to the United States divided the archipelago into two parts: the Russian-American maritime border passed along the strait between the two islands.

Since 1916, due to the weak protection of the northern borders, an American trading post was illegally operating on the island, which did not pay customs duties. In September 1925, the frontier patrol ship Vorovskiy arrived at Big Diomede Island, after which the Americans were forced to leave Soviet territory. In 1941, a frontier post was established on the island.

From 1905 to 1933, a gradual migration of indigenous people to the neighboring American island of Kruzenstern took place from Big Diomede Island. The inhabitants of the settlement of Kunga, which existed in the north of the island, completely moved to Little Diomede from 1905 to 1915. With the beginning of the Cold War, in 1948, through the efforts of the Soviet side, the remaining residents (about 30 people from the settlement of Imaklik, located in the south of the island) were forcibly resettled to the mainland of Chukotka, to the village of Naukan, which was also resettled ten years later as part of the policy of “enlargement ".

In 2005, a seven-meter Orthodox cross was erected on the highest hill of the island (Mount Krysha), which is clearly visible to residents of neighboring Alaska and ships passing through the Bering Strait.

In September 2016, the island was visited by Patriarch Kirill of Moscow and All Russia.

At various times, it was planned to pass a tunnel through the island, which would connect Eurasia and North America.



One of the largest bird colonies in the region is located on Ratmanov Island, with a total of 11 species of seabirds with a total population of over 4 million individuals. In June 1976, an ocher hummingbird was observed here - the only hummingbird species recorded in Russia.

There is a large walrus rookery on the island, and massive migrations of gray whales take place in the coastal waters.