Historically the languages were spoken over a larger area: west to the mouth of the Vistula river in present-day Poland, at least as far east as the Dniepr river in present-day Belarus, perhaps even to Moscow, and perhaps as far south as Kyiv. Key evidence of Baltic language presence in these regions is found in hydronyms (names of bodies of water) that are characteristically Baltic. The use of hydronyms is generally accepted to determine the extent of a culture's influence, but "not" the date of such influence.