Sandanski is located in the
Sandanski–Petrich Valley, surrounded by the
Pirin,
Belasitsa and
Ograzhden mountain ranges. The town is about 160 km south from Bulgaria's capital
Sofia along the major
European Route E79. Following the same route at almost the same distance is
Thessaloniki, Greece's second largest city. Sandanski has developed in an amphitheatrical fashion on the outer south-west flanks of the Pirin Mountains along the lower reaches of
Sandanska Bistritsa River. The town's altitude varies between 240 and 300 meters. Its geographical location between
Kresna and
Rupel Gorges determines the town's mild winter and unpleasant summer temperatures. Statistically, Sandanski has the warmest temperatures in Bulgaria, with a total of around 2700 annual sunshine hours. Within a short drive from Sandanski is
Melnik, the smallest town in Bulgaria in terms of population, but an attractive tourist destination for its authentic architecture and wine production. In close proximity is the village of
Rozhen and the
Rozhen Monastery. The
Ancient Roman city of
Parthicopolis was located nearby.
Climate Sandanski has a
temperate climate (Köppen Climate Classification: Cfa). Summers are very hot and dry with occasional thunderstorms, and during heat waves the temperature may exceed 40 °C reaching to 45 °C, the highest recorded temperature in the city. Winters are damp and relatively mild, lasting for about three months from December through February. Springs and falls are generally about two months each. The summer is the longest season in Sandanski, lasting 4 months – from early June to late September. Precipitation is evenly distributed throughout the year except for July and August when droughts often occur.
Climate table: {{Weather box ==Municipality==