Balkan mountain range
The Balkan Mountains run through the center of Bulgaria. They are the longest mountain range in Bulgaria and divide the country into northern and southern regions.
Stara Planina
Varna
The Appenines mountain range runs through most of the Italian Peninsula.
The Balkan mountain range runs from the border with Serbia 560km eastwards to the Black Sea
These are the Carpathian Mountains.
Its the Danube river and Danube plain separates Romania and Bulgaria. There are no mountaneous border between the mentioned two countries. And Carpathian mountain range of Romnia or Balkan mountain range (most northern mountains of Bulgaria: none of them serves as border.
pindus mountains
The Balkan Mountain range (in Bulgaria Balkan Mountain is often called the 'Stara Planina' Mountains)
The Stara planina mountain (Стара планина)
that is the apennines that is right in the center of Italy.
Balkan mountain range, The Daniube and a capital Sofia!