Mineral springs are in great abundance located mainly in the southwestern and central parts of the country along the faults between the mountains. These include the Rila primrose, Balkan violet, Bulgarian blackberry and Rhodopean tulip.
Forests have wild fruits, briars, blueberries, blackberries, raspberries, strawberries and mushrooms, as well as a variety of herbs and healing plants. Pelicans, stags, deer, wild goats, quail, and pheasants populate reserves and hunting grounds.
The Rila mountains include the highest peak of the Balkan Peninsula, Musala, at 9,596 feet (2,925 meters).
In 1991 Bulgarian environmentalists estimated that 60 percent of the country's agricultural land was damaged by excessive use of pesticides and fertilizers and by industrial fallout.
In 1991, two thirds of Bulgarian rivers were polluted, and the Yantra River was classified as the dirtiest river in Europe.
By that time, about two-thirds of the primary forests had been cut.
Two especially sensitive areas are in the Gorna Oryahovitsa area in north-central Bulgaria, and a wide area extending through the Rila and northern Pirin regions to Plovdiv in south-central Bulgaria.
Sixteen major earthquakes struck Bulgaria between 19, the last two in Strazhitsa on the Skopje-Razgrad fault line.