Bulgaria is the Balkan territory that has better defined and wider natural regions. Their originality essentially consists in the fact that, unlike the other countries of the peninsula, they take the O.-E. direction, that is, they follow the tectonic motif of the Balkans. Running almost parallel to the Danube for about 600 km., From Timok to M. Nero. With an average width of about 30 km., The Balkans (in Bulgarian Stara Planina, or “old mountain”) reveal a marked contrast between the northern side, which descends in steps on the Danube plain, and the one facing south, marked by faults. The whole system can be divided into three sections, quite different in their characters. The western one, which arches sharply towards the NE. to the furrow of Iskăr, and consists mostly of paleozoic soils, with red limestone and sandstone that the meteoric waters have engraved in characteristic forms of erosion (Belogradčik cliffs), it rises as you proceed towards the SE. (Midžor, m. 2186, Dabišin Vărh m. 2180); the power station, which takes a direction almost exactly W-E, is marked by the highest elevations of the system (Jumruk Čal m. 2371, Kademlija m. 2273) and is more rugged, more alpine, more picturesque; the eastern one, from Demirkapija to M. Nero, resulting mainly from sandstones and tertiary sediments, is divided into two or three parallel chains, also vaults from O. to E., of very modest height (generally not exceeding 500 m.). erosion (Belogradčik cliffs), it rises as you proceed towards the SE. (Midžor, m. 2186, Dabišin Vărh m. 2180); the power station, which takes a direction almost exactly W-E, is marked by the highest elevations of the system (Jumruk Čal m. 2371, Kademlija m. 2273) and is more rugged, more alpine, more picturesque; the eastern one, from Demirkapija to M. Nero, resulting mainly from sandstones and tertiary sediments, is divided into two or three parallel chains, also vaults from O. to E., of very modest height (generally not exceeding 500 m.). erosion (Belogradčik cliffs), it rises as you proceed towards the SE. (Midžor, m. 2186, Dabišin Vărh m. 2180); the power station, which takes a direction almost exactly W-E, is marked by the highest elevations of the system (Jumruk Čal m. 2371, Kademlija m. 2273) and is more rugged, more alpine, more picturesque; the eastern one, from Demirkapija to M. Nero, resulting mainly from sandstones and tertiary sediments, is divided into two or three parallel chains, also vaults from O. to E., of very modest height (generally not exceeding 500 m.). more picturesque; the eastern one, from Demirkapija to M. Nero, resulting mainly from sandstones and tertiary sediments, is divided into two or three parallel chains, also vaults from O. to E., of very modest height (generally not exceeding 500 m.). more picturesque; the eastern one, from Demirkapija to M. Nero, resulting mainly from sandstones and tertiary sediments, is divided into two or three parallel chains, also vaults from O. to E., of very modest height (generally not exceeding 500 m.).
On the whole, the range shows forms rather of the average than of the high mountain, with gentle and rounded summits, generally steep slopes, wide undulating shelves that provide good pastures (Č al); it lacks glacial traces and offers easy transit through numerous passes.
At N. of the Balkans, preceded by a large hilly strip that fringes them with greater amplitude the further one proceeds towards the E., the wide cretaceous plateau opens towards the Danube, consisting of a surface with horizontal or slightly inclined lines. The rivers descending from the Balkans divide one and the other into a series of minor units, completely similar morphologically. The valleys that separate them, with their characteristic wide and flared profile, corresponding to fractures, are asymmetrical, with the right margin higher. The arenaceous-calcareous base remains hidden by a thick mantle of decaying clays and humus, which gives a porous, fertile soil, suitable for the cultivation of cereals, but gives the landscape the monotonous and gray aspect of the Pontic steppe. In its extreme SE portion. the Danube plateau and the hilly area that precedes it fade into central Dobruja, Deli Orman and the region between Provadiiska Planina and Kamčij, the first flat and bare, the second rough and wooded, the last engraved by deep furrows, which heralds already the relief of the Balkans. The morphological landscape is characterized here by the development of karst phenomena and the resulting hydrographic network.
The Bulgaria of SO., Formed by the Rodope massif, which extends between Marizza and Struma, presents a completely different character. This is the most compact and highest mountainous area not only in Bulgaria, but in the whole peninsula. The peaks approach 3000 m. so in the Rila group (Mus Allah, m. 2926, the highest in Bulgaria, Juruški Čal, m. 2774, Popova Šapka, m. 2699), as in that of Pirin (El Tepè, m. 2930, Ala Burun, m. 2206). Overall, the massif constitutes a real barrier between the eastern, western and central regions of the Balkan. Especially the Rila and Pirin groups remember – for the harshness of the slopes, the deep valleys and marked by thresholds, the sharp and daring peaks, the snows that persist there until almost summer, the development of glacial traces (circuses, moraines, lakes: of these, about a hundred in the Rila, about forty in the Pirin), the grandeur of the woodland – the high alpine alpine landscape. The various sections of Rodope, no less than the Pirin and the Rila, appear clearly identified by means of the high tectonic basins (Samokov, Dupnica, Razlog, Džumaja) and by the valleys embedded and interrupted by gorges (Struma, Mesta, Veka, Arda and their tributaries), which at the same time constitute their only communication routes.
Unlike the Balkans, the Rodope group looks like a real labyrinth of mountain spurs, directed in every direction. The long peak that flanks the course of the Mesta forms, with what serves to separate the Arda from the tributaries of the upper Marizza (central Rodope), a wide triangle, with the base aimed at the latter. The elevated crystalline base is surmounted towards the W by the highest elevations of the system (Sjutke, m. 2188, Karlăk, m. 2082). Towards the E. the sunken and winding valleys that affect it alternate more or less vast mountain basins (Čepino, Stanimaka) and large meadows, while the height of the peaks decreases, until they drop below 600 m. in the region of the middle Marizza. Only the southernmost spurs, which run along the current Greek border and mark the watershed between the Arda and the rivers flowing directly into the Aegean, again exceed 1500 m. (Kušlar Dag, m. 2177; Karlăk, m. 1900).
Continuation of the Rodope we can consider the reliefs that form the right side of the shower where the Struma runs. With the Osogovs (Ruen, m. 2225) you enter an area of tectonic basins of various sizes, more or less clearly delimited by mountain ranges, covered on the bottom by tertiary lake depositions and marked on the margins by fracture lines. The region, which continues to N. up to the Nisava furrow, is crossed by the upper courses of the Struma, Iskăr and their tributaries; the resulting hydrographic connection translates into a very relative ease of communication, because as a rule the erosive notches that intercede between the basins themselves hinder the passage from one to the other, rather than facilitate the passage from one to the other.. Of the basins (Samokov, Pernik, Kjustendil,
The elevated and picturesque Sienite massif of Vitoša (Černi Vărh, m. 2285), which forms the background towards the south of this plain, joins beyond the Iskăr with the Ihtiman group, who begin a long and narrow band of reliefs, stretches parallel to the Balkans from Sofia to Tungia and overall called Srednja Gora. Much lower than the Balkans (Bogdan, m. 1573, Bunaja, m. 1566), the Srednja Gora essentially reproduces its characters. The Cenozoic corrugation, which determined its detachment from the opposite chain, interposed, between one and the other, a depressed area, which low saddles separate into several trunks or smaller units (basins of Zlatica, Karlovo, Kazanlăk, Slivno). The height of these decreases towards the east (Zlatica 750, Slivno 150 m.), where the last undulations of the chain join with the southern offshoots of the Balkans. The basins of Karnobat, Aitos, Anhiolo can be considered as the morphological continuation of those, which they also resemble for other characteristics (climate, vegetation). It is a series of closed basins, in which maritime influences penetrate very little, and instead dominate the continental ones; in the humid alluvial bottoms, more than the cultivation of cereals, some industrial plants, fruit trees and above all grapevines find suitable conditions, which show a lesser diffusion to the north of the Balkans. Some of these plains, such as Fr. ex. the Tulovsko Pole of Kazanlăk, are famous for their rose gardens. which they also resemble for other characters (climate, vegetation). It is a series of closed basins, in which maritime influences penetrate very little, and instead dominate the continental ones; in the humid alluvial bottoms, more than the cultivation of cereals, some industrial plants, fruit trees and above all grapevines find suitable conditions, which show a lesser diffusion to the north of the Balkans. Some of these plains, such as Fr. ex. the Tulovsko Pole of Kazanlăk, are famous for their rose gardens. which they also resemble for other characters (climate, vegetation). It is a series of closed basins, in which maritime influences penetrate very little, and instead dominate the continental ones; in the humid alluvial bottoms, more than the cultivation of cereals, some industrial plants, fruit trees and above all grapevines find suitable conditions, which show a lesser diffusion to the north of the Balkans. Some of these plains, such as Fr. ex. the Tulovsko Pole of Kazanlăk, are famous for their rose gardens. of fruit trees and especially of vines, which show a lesser diffusion in the N. of the Balkans. Some of these plains, such as Fr. ex. the Tulovsko Pole of Kazanlăk, are famous for their rose gardens. of fruit trees and especially of vines, which show a lesser diffusion in the N. of the Balkans. Some of these plains, such as Fr. ex. the Tulovsko Pole of Kazanlăk, are famous for their rose gardens. For Bulgaria 2003, please check computerannals.com.
The Srednja Gora and the Rodope isolate the large basin of the Marizza, flared towards the E. and SE., The largest and at the same time most complete morphological unit of the peninsula. Genetically analogous to the pre-Calcanic valleys, it is distinguished by its unparalleled larger proportions, by the greater power of alluvial deposits, and above all because it is open to southern influences, and therefore to those of the Mediterranean climate. It is divided into two almost equal parts of extension. To the west is the plain of Plovdiv (Plovdiv) in the bottom of which the Marizza wanders slowly between low banks; fertile territory suitable for all kinds of crops: vineyards and fields, orchards and rice fields, meadows and woods alternate in a rich and pleasant landscape, rightly considered one of the most beautiful in Bulgaria. Its eastern continuation, which can be called from Stara Zagora or from Haskovo, it lacks the hydrographic unit that characterizes the upper basin of the Marizza. More than a plain, it corresponds to a sensibly moved territory, inclined in complex towards the S. and closed to the East. by the hills that flank the lower course of the Tungia. The latter bind to SO. with the gneissic mass of the Sakar Planina, lying between the Marizza and Tungia, at S. di Jambol. Further to the East. the crystalline nucleus, of which they represent a remnant, emerges in the flat relief of the Strandža, of which only a small section falls within the borders of Bulgaria. from the hills that flank the lower reaches of the Tungia. The latter bind to SO. with the gneissic mass of the Sakar Planina, lying between the Marizza and Tungia, at S. di Jambol. Further to the East. the crystalline nucleus, of which they represent a remnant, emerges in the flat relief of the Strandža, of which only a small section falls within the borders of Bulgaria. from the hills that flank the lower reaches of the Tungia. The latter bind to SO. with the gneissic mass of the Sakar Planina, lying between the Marizza and Tungia, at S. di Jambol. Further to the East. the crystalline nucleus, of which they represent a remnant, emerges in the flat relief of the Strandža, of which only a small section falls within the borders of Bulgaria.
The position of the Marizza basin explains why it was subject more than any other region of the peninsula to Byzantine and then Turkish influences, thus differentiating itself in many respects (remember the name Rumelia) from northern Bulgaria. The cultivation of cereals is joined or even replaced by that of tobacco, cotton and plants that find a place in the Balkan valleys, while in the hilly areas, better sheltered and more densely inhabited, those of vines and mulberries are widespread.