Momina Klisura Gorge of the river Maritsa to the town of Belovo. From Belovo begins its border with the Upper Thracian Plain, which roughly follows a line through the settlements of Vetren, Kalugerovo, Blatnitsa, Krasnovo, Starosel, Chernichevo and reaching the river Stryama at the village of Pesnopoy. From there it continues further east close to the villages of Varben, Zelenikovo and Veren, from where the Chirpan Heights from a bulge in southern direction to the town of Chirpan and then the mountain range continues eastwards near Stara Zagora, Korten and Kamenovo, reaching the elevation of Zaychi Vrah northwest of Yambol. Division Sredna Gora is divided in three parts by the rivers Topolnitsa and Stryama, both left tributaries of the Maritsa — Ihtimanska Sredna Gora to the west, Sashtinska Sredna Gora in the middle and Sarnena Sredna Gora to the east. Ihtimanska Sredna Gora is limited to the west by the valley of the Iskar, to the north by the valleys of Sofia, Saranska, Kamarska and Zlatitsa–Pirdop, to the east by the Topolnitsa, to the south by the Rila mountain range. It is subdivided in three sections — Vakarelsko–Belishki, Shipochansko–Eledzhiski and Ihitmanski. The first section includes the mountains of Lozen (1,190 m) which is the westernmost point of the whole mountain range, Vakarelska (1,090 m) and Belitsa (1,221 m). The river Gabra forms a small valley between Lozen and Vakarelska. Shipochansko–Eledzhiski section is located between the Samokov Valley in the west and the Topolnitsa in the east and links with Rila and Konstenets–Dolna Banya Valley in the south. It includes the ridges of Shipochanski Rid (1,312 m), Shumnatitsa (1,392 m), Septemvriyski (1,275 m) and Eledzhik (1,186 m). Between these two sections is situated the Ihtiman Valley at an altitude of 650 m. Sashtinska Gredna Gora spans from the valley of the Topolnitsa in the west to the river Stryama in the east. It is limited to the north by the southern reaches of the Zlatitsa–Pirdop and Karlovo valleys, and to the south by the Upper Thracian Valley. It is subdivided in two sections — Bunaysko–Bogdanski and Panagyursko–Strelchanski. The former is the highest past of the mountain range and is located to the north. From west to east it includes the summits of Bratia (1,519 m), Bunaya (1,572 m) and Golyan Bogdan (1,604 m). In its middle is located the high altitude Koprivshtitsa Valley (1,000 m). The elevation lowers to the south