Complex sentence: The Vilkitsky Strait runs south of Starokadomsky and Maly Taymyr and its waters, as well as the waters surrounding the two islands, are covered with pack ice during the long and bitter winters.
Split into simpler sentences: The Vilkitsky Strait runs south of Starokadomsky and Maly Taymyr. Its waters, as well as the waters surrounding the two islands, are covered with pack ice during the long and bitter winters.