From the Taurus we descended firstly to the north of Syria, because in the development of Hittite studies this region first attracted attention through the references to it in Egyptian and Assyrian history. But modern research has added to our knowledge of the Hittite lands a wider and different territory on the other side. There the descent to the interior of Asia Minor from the mountains is not so marked, for even around the foot of snow-capped Argæus, the most advanced pinnacle of the system, the plateau is still four thousand feet above the sea. The level falls gradually towards the west, but rarely much below three thousand feet; while on the other hand the numerous minor ranges that break the surface of the interior attain a considerably greater height. This tableland is almost enclosed by ridges of mountains: on the north and south these descend directly to the coast; on the west they are more broken and less bold, but they constitute none the less a great obstacle between the plateau and the green valleys of the Ægean coast.[20] On the east, as we have already seen, are the Anti-Taurus ranges, backed by the Armenian hills beyond. The upland area thus enclosed is from two to three hundred miles across according to the direction taken, for its form is irregular. Only to the south is the boundary sharply defined, where the range of Taurus forms a mighty wall, which in the middle turns almost a right angle in direction, running north-eastward and north-west. The whole plateau may be regarded as irregularly five-sided. The interior varies greatly in its features, the chief agent being the peculiarities of its river systems. Shut in as it is, many rivers fail to find an outlet to the sea: this is especially the case in the plain which lies at the foot of the western ranges of the Taurus, where the waters stagnate, forming salt lakes or marshes. This plain is green around Konia, but its extensions to the north and east are practically desert, being parched and barren in the summer months. On its north-east, in the centre of the peninsula, its boundary is the largest salt lake of the interior, which is fed likewise by several minor inland streams. There are some rivers, however, which find an outlet even through the Taurus ranges, but such are more common towards the west and north-west. The districts which these water are consequently among the most attractive of Asia Minor, with areas of natural woodland and green pastures, as well as fertile soil for cultivation.