Geographic map of the Balkan Mountains (in Bulgarian). Geographic limits of the map:
Own work

Sources of data:Topography: NASA SRTM3 (public domain);
Rivers and water bodies: Produced using Copernicus data and information funded by the European Union - EU-Hydro layers &amp; USGS HydroSHEDS database
Borders and towns: © OpenStreetMap contributors
Tool:The map is created with Octave scripts developed by Ikonact
Ikonact