The Bering Strait is all that separates the US state of Alaska from Russia, and at its narrowest point they’re only 51 miles (82 kilometers) apart, but there is currently no bridge that crosses the Bering Strait, and there are some very good reasons why. But a crossing between Alaska and Russia isn’t impossible, and in the future, the continents of Asia and North America could end up being connected via bridge or even a tunnel.