The Pirin Mountains are a mountain range in southwestern Bulgaria, with the highest peak, Vihren, at an altitude of 2,914 m (9,560 ft).

Vihren is the highest peak of Bulgaria's Pirin Mountains. Reaching 2,914 metres (9,560 ft), it is Bulgaria's second and the Balkans' third highest, after Musala and Mount Olympus. Although Vihren is deprived of lakes and streams due to the karst topography, a number of Pirin's lakes are located around the peak, as is Europe's southernmost glacial mass, the Snezhnika glacieret. Until 1942 Vihren was known as Eltepe ; it was also called Buren (stormy) and Malnienosets (lightning-bringer). The UNESCO World Heritage Site Pirin National Park was originally known as the Vihren National Park. Vihren is included in the 100 Tourist Sites of Bulgaria under No. 2.