What topography is there in Bulgaria?

With a territory of 110,994 square kilometers (42,855 sq mi), Bulgaria ranks as the 16th-largest country in Europe. Several mountainous areas define the landscape, most notably the Stara Planina (Balkan) and Rodopi mountain ranges, as well as the Rila range, which includes the highest peak in the Balkan region, Musala. In contrast, the Danubian plain in the north and the Upper Thracian Plain in the south represent Bulgaria's lowest and most fertile regions. The 378-kilometer (235 mi) Black Sea coastline covers the entire eastern bound of the country.
Geographically and in terms of climate, Bulgaria features notable diversity, with the landscape ranging from the Alpine snow-capped peaks in Rila, Pirin and the Balkan Mountains to the mild and sunny Black Sea coast; from the typically continental Danubian Plain (ancient Moesia) in the north to the strong Mediterranean climatic influence in the valleys of Macedonia and in the lowlands in the southernmost parts of Thrace.
Bulgaria comprises portions of the separate regions known in classical times as Moesia, Thrace, and Macedonia. About 30% of the land is made up of plains, while plateaus and hills account for 41%.[56] The mountainous southwest of the country has two alpine ranges-Rila and Pirin-and further east stand the lower but more extensive Rhodope Mountains. The Rila range includes the highest peak of the Balkan Peninsula, Musala, at 2,925 meters (9,596 ft);[57] the Balkan mountain chain runs west-east through the middle of the country, north of the Rose Valley. Hilly countryside and plains lie to the southeast, along the Black Sea coast, and along Bulgaria's main river, the Danube, to the north. Strandzha forms the tallest mountain in the southeast. Few mountains and hills exist in the northeast region of Dobrudzha.