Topoguide (en anglais) de l'éditeur Cicerone avec avec des fiches détaillées pour randonner dans les parcs nationaux de Bulgarie.

Description fournie par l'éditeur :
A guidebook to 12 multi-day treks in Bulgaria's highest and wildest mountain ranges in the Pirin, Rila and Central Balkan national parks. The treks are aimed at fit, experienced mountain walkers, with steep ascents and exposed scrambles. The routes range from 7 to 61 km and include a full-day ascent of Mount Vihren.
Seasons : Snow can be a hindrance until the end of June; wildflowers at their peak in July; August and September have stable sunny weather; early October is great for photography; not safe in winter due to avalanche risk.
Centres : Teteven, Divchovoto, Apriltsi, Troyan, Kalofer, Karlovo, Sevlievo, Kazanlak, Rila Monastery, Samokov, Malyovitsa, Govedartsi, Borovets, Kostenets, Bansko, Razlog and Melnik.
Difficulty : Walks are suitable for fit and experienced mountain walkers; long steep ascents and descents, often over rocks and boulders; most of the ridge walks require a good head for heights, especially the Koncheto crest and the ascent of Vihren.
Must See : Ancient beech forests of the Boatin reserve; traverse of the Triglav massif; rock outcrops of the Sokolna reserve; Rila Monastery; Malyovitsa ridge walk; Musala (2925m); Melnik Pyramids; Rozhen Monastery; the Koncheto crest; Vihren (2914m); outstanding birdwatching; exceptional variety of butterflies.