THE IBERIAN PENINSULA 669

the sea have been few. Where coastal plains exist, they are usually
narrow, and mountains or the abrupt edge of the plateau render con-
tacts with the interior very difficult. The major portion of the popula-
tion consequently had little interest in or knowledge of the sea. Even
during the days of Iberian supremacy, and at the period when trade
routes were most favorable, such maritime activities as were carried
on seem to have been the result of a conscious effort rather than a
natural growth. Only the people of the Portuguese plain have main-
tained an interest in the sea, and this consists largely in carrying on
coastal trade. This lack of commercial interests and development has
isolated the peoples of the peninsula culturally and economically, and
has made it difficult for them to take advantage of such favorable
locational factors as have existed.

CLIMATE

The location of the peninsula causes most of it to be within the
dry horse latitudes and trades in the summer, and within the prevailing
westerly belt in the winter. Rainfall is accordingly seasonal, coming
largely during the autumn and winter. A deficiency of rainfall charac-
terizes most of the land, and limits agriculture. In this the peninsula
would seem to conform with the other Mediterranean lands. But in
spite of the fact that the sea forms seven-eighths of the boundaries of
the peninsula, bordering mountains and an average elevation of some
2200 feet restrict the moderating influence of the water, and give the
greater part of the land a continental climate. Thus, in contrast to most
Mediterranean lands, it is a region of extremes in temperature. How-
ever, relief and latitude cause the peninsula to be divided into four
climatic zones, each of which has a distinct influence on vegetation
and human development.

The highlands of the north and the northwest have a climate en-
tirely different from the rest of the peninsula. Cool summers and mild
winters, with heavy and evenly distributed rainfall, favor forest
growth, the raising of forage crops, and dairying. The climate and the
resulting types of agriculture thus resemble those of northwestern
Europe. This same type of climate extends south along the western
seaboard as far as central Portugal.

The "meseta" or plateau which occupies about three-fourths of
the peninsula has an< extreme continental climate, with light rainfall
coming mostly during the winter. The rainfall is a little heavier in the
northwestern portion of the plateau, and here is located the great