While most maps show Russia and the United States on opposite sides of the world, they are actually incredibly close neighbors. In the middle of the Bering Strait lie two islands: Big Diomede (Russia) and Little Diomede (USA). The distance between these two islands is only about 2.4 miles (3.8 kilometers). During the winter, an ice bridge sometimes forms between them, meaning one could technically walk from the US to Russia in about 20 minutes. Adding to the trickiness, the International Date Line runs between the two islands, meaning Big Diomede is 21 hours ahead of Little Diomede despite being within walking distance. This makes them 'Tomorrow Island' and 'Yesterday Isle.'