The western part of the sandstone Carpathians which lies within Ukrainian territory is called the Low Beskid. It is also known as Lemkivski Beskid because it is inhabited by the Ukrainian mountain tribe of the Lemkes. The Low Beskyd extends from the defile of Poprad to the valleys of the Strviazh River, the Oslava (Lupkiv pass), and the Laboretz. It is a broad -backed but not a' high mountain country. In long chains, gently undulating mountain ridges stretch from west to east and southeast. Their slopes are gentle; one can easily walk or even ride up, and numerous wagon-roads and highways lead straight over the crest or even along the edge of the crest. The peaks are rounded and of uniform height, except where an occasional gently vaulted mountain top rises above the low-hill country. Between gently sloping ranges there extend, in a longitudinal direction, valleys with watersheds and communicating passes. Broad, well-developed defiles separate the range into different sections. The Galician- Hungarian dividing-ridge has only slight gorges of genuine mountain passes.
The peaks and high passes of the Lower Beskid are insignificant. Only in the extreme west, on the Poprad and the Torissa,do the peaks reach a height of 1000 and 1 100 m.; further toward the east hardly 700 to 800 m. The important Dukla Pass is hardly 500 m. above sea-level. In the middle of the Beskid mountain country we even see a great longish strip of lower country ("the Sianok Lowlands") whose low hills are less than 300 m. high.
There is a connection between the insignificant height and soft landscape forms of the Low Beskid and the geological construction and evolution of the mountain range. This mountain country, like the whole sandstoneregion of the Carpathians, is built up of strongly plicate and compressed Flysch — a series of sandstones slates, conglomerates, clays, etc., of the cretacian and tertiary ages. All these species of rock occur in this region in thin layers and have little power of resistance; everywhere the basic mountain ridge is covered with a thick coat of weathering loam; rock piles are found very seldom. There is added the fact that all the sandstone Carpathians of the Ukrainian territory have been evened out by the destructive action of water and air into a more or less perfect plain. Not until the quaternary was the "obliterated" range raised anew and transformed into a mountain district by the action of the rivers which were cutting in again.
The Low Beskid was once covered with great, mixed forests. Now the once splendid virgin forests are completely thinned and all the ill effects of forest destruction have visited the poor mountain country. The fertile soil was washed away on the mountain-sides and heaped up with rubble and mud in the valley bottoms. The tribe of the Lemkos is therefore, perhaps, the poorest of all the Ukrainians and is compelled to seek an existence in distant lands.
In the southern part of the Low Beskid the boundaries of the Ukrainian nation in Hungary reach the northern part of the Hegyalia-Sovari Ridge, which, at this point, is 1100 m. high, and is composed of extinct trachyte volcanoes.
To the east of the Lupkiv Pass begins the second section of the Ukrainian Carpathians — the High Beskid. It stretches to the southeast as far as the valleys of the Stri, Opir and Latoritza Rivers (Pass of Verezki).
The High Beskid like the Low is composed of a number of parallel, weakly joined mountain ranges, which run northwest and southeast. The type of the Rost Mountains is, therefore, even more clearly marked in this part of the sandstone Carpathians than in the preceding. The mountain crests are gently sloped, the edge of the crests slightly curled, the height of the peaks constant, the passes only walled passes. Toward the southeast, tho, the ridge steadily increases in height. The highest peaks are Halich (1335 m.), the beautifully pyramid-shaped rocky Piku (1405 m.) and the massive Polonina ruvna (1480 m.). In the Flysch of the High Beskid, two species of sandstone attain greater power of forming layers and of resisting pressure — the chiefly upper cretacian Yamna sandstone and the oligocene Magura sandstone. The former forms beautiful groups of rocks on peaks and precipices. The cliffs of Noich, with its traces of a rock castle, are the most famous.
The longitudinal valleys are much less developed in the High Beskid than in the Low. They are traversed only by smaller brooks. All larger streams like the Strviazh, Dniester and Opir, flow thru well-formed passes. Expansions of valleys (in regions of soft slate) alternate with contractions of valleys (in regions of hard sandstone). Most remarkable are the deeply cut out winding valleys (San, Striy), which offer the best proof of the former smoothing down and the later raising of the mountains.