The Bering Strait is the body of water separating the North American continent (Alaska, United States) from the Asian continent (Chukotka Peninsula, Russian Federation). This narrow maritime passage connects the Arctic Ocean’s Chukchi Sea to the Pacific Ocean’s Bering Sea. The strait represents one of the most physically confined international boundaries in the world. The proximity of these landmasses has shaped the region’s history, climate, and human migration.
The Closest Point and Measurement
The minimum distance between the continental mainlands of North America and Asia is measured between Cape Prince of Wales, Alaska, and Cape Dezhnev, Russia. The distance across the Bering Strait at this point is approximately 51 to 53 miles (82 to 86 kilometers). This span marks the boundary between the westernmost American mainland and the easternmost Eurasian mainland. The water depth in the strait is quite shallow, typically ranging from 100 to 160 feet (30 to 50 meters). This shallow depth contributed to the region’s ancient geological history.
The Diomede Islands Geography
The Diomede Islands dramatically shorten the gap between the two nations. These two small, rocky outcroppings sit in the middle of the strait, acting as stepping stones between the continents. Big Diomede belongs to Russia, and Little Diomede is United States territory.
They are separated by only 2.4 to 2.7 miles (3.8 to 4.3 kilometers) of water, representing the shortest distance between the U.S. and Russia. The international boundary and the International Date Line pass directly through this narrow channel. The date line creates a notable temporal difference, giving the islands unique nicknames. Big Diomede is referred to as “Tomorrow Island,” while Little Diomede is called “Yesterday Island.”
Historical Context and Border Implications
For much of human history, the Bering Strait was not a body of water. During the last Ice Age, lowered sea levels exposed a vast landmass known as Beringia, or the Bering Land Bridge. This land bridge was up to 620 miles (1,000 km) wide and served as a route for the first human migration into the Americas, beginning approximately 30,000 to 15,000 years ago.
The modern border was legally established with the 1867 Alaska Purchase, when the United States acquired the territory from the Russian Empire. This transaction set the political boundary through the Bering Strait, formally separating the two nations. Prior to this, Indigenous peoples, including the Yupik and Inupiat, moved freely across the strait for trade and cultural exchange.
The maritime boundary, sometimes called the “Ice Curtain” during the Cold War, still governs fishing rights and security patrols. The boundary ensures close monitoring of the passage, especially as commercial and scientific traffic increases due to melting Arctic ice.
Seeing Across the Bering Strait
It is possible to see the Russian mainland from the American side of the Bering Strait on a clear day. From Cape Prince of Wales, the Russian Big Diomede Island is visible. Standing on Little Diomede Island provides an unobstructed line of sight to its Russian counterpart, Big Diomede, just miles away.
The mainland-to-mainland distance is too great for casual swimming, but the smaller gap between the Diomede Islands has been successfully crossed by extreme athletes. In 1987, American swimmer Lynne Cox completed the 2.7-mile swim from Little Diomede to Big Diomede in the frigid water. The water temperature in the strait averages near freezing, between 36 and 50 degrees Fahrenheit, even in summer.
In winter, the surface of the Bering Strait can freeze over, forming a temporary ice bridge. However, currents and wind keep the ice dynamic. Unauthorized crossings on foot or by vehicle during the winter freeze are illegal and extremely dangerous. The challenge of the Bering Strait involves not only the cold water but also the strong, unpredictable tidal currents flowing between the Pacific and Arctic oceans.