From whatever point you penetrate into the Spanish peninsula, you will find yourself confronted almost at once by a region of hills; you will then enter into a labyrinth of valleys, gorges and ravines; and finally, after a longer or shorter ascent, you will emerge upon the central tableland, barred by the naked sierras whose wide and deep valleys form the mighty cradles of mighty rivers. Across this tableland stretches Castile, the land of castles. Like all great expanses of earth, this tableland receives and irradiates heat more quickly than the sea and the coast-lands which the sea refreshes and tempers. Hence, when the sun scorches it, an extreme of heat, and as soon as the sun forsakes it, an extreme of cold; burning days of summer followed by cool fresh nights during which the lungs gratefully inhale the breeze from the land; freezing winter nights following hard upon days which the bright cold sun in its brief diurnal course has failed to warm. Winters long and hard and summers short and fiery have given birth to the saying, “_nueve meses de invierno y tres de infierno_”--nine months of winter and three months of hell. In the autumn, however, there is a serene and placid breathing-space. The sierras, shutting out the winds from the sea, help to make the winter colder and the summer hotter; but while they impede the passage of the gentle low-trailing clouds they form no barrier to the violent cyclones which burst among their valleys. Thus long droughts are succeeded by torrential deluges. In this severe climate of opposing extremes, in which the transition from heat to cold and from drought to flood is so violent, man has invented the cloak with which to isolate himself from his environment, a personal ambience, constant in the midst of external changes, a defence at once against both heat and cold. The great storms of rain and snow bursting upon these sierras and drained thence by the swollen rivers have in the course of centuries scoured the soil of the tableland, and the succeeding droughts have prevented the retention of the rain-washed soil in a network of fresh and robust vegetation. Thus it is that the view presents a wide and desolate expanse of burning country, without foliage and without water, a country in which a deluge of light throws dense shadows upon a dazzling surface, extinguishing all intermediate tones. The landscape is seen cut out in hard outline, almost without atmosphere, through a thin and transparent air.