The members of the "modern" snake families Colubridae, Viperidae and Elapidae (representatives of the family Colubridae appeared in Europe as the first) might have penetrated into the areas of Central Europe probably across the Mazury -Mazowsze continental bridge. The "modern" families penetrated into West Europe across the Rhine Graben by several immigration waves. Based on the known marine incursions into the Rhine Graben and adjacent areas, a total of four distinct waves of dispersal of both the Asiatic and North American immigrants can be discerned within the Early Oligocene - Middle Miocene time span. The Early Miocene (MN 1 - MN 2a) and the Early / Middle Miocene (MN 3 - MN 4/5) dispersals of snakes are responsible for the final displacement of representatives of the "ancient" family Boidae out of West and Central Europe. The Early and the Middle Miocene migrations have likewise initiated the evolution of the modern European snake fauna.