Here's the Russian-American Frontier Most Americans thinks of Russia and Asia as far away---But there is just three miles between the Easternmost Russian Territory, and the Westernmost Alaska Land. The International Boundary between Siberia and America Lies between the Big and Little Diomede Islands, which are three miles apart, and 22 miles from the Alaskan Mainland. Big Diomede, at the right, is Russian Domain, and the Soviet land is reported building an important air base. February 8, 1940. (Photo by ACME Newspictures Inc.)