The "Eurosiberian" Atlantic zone extends through northern Portugal, the Galician Massif, Cantabrian Mountains and the western and central Pyrenees. It is characterized by a humid climate which is moderated by the influence of the ocean, with somewhat cold winters and the lack of a distinct dry season. The mainland extends to the north of Portugal, the greater part of Galicia, Asturias, Cantabria, the Basque Country, northwest of Navarre, and western Pyrenees. However, its influence in the form of communities or defined species extends inwards, especially in the north and west.