Named after the Macedonian Bulgarian revolutionary Yane Sandanski, it is situated in Sandanski–Petrich Valley at the foot of Pirin Mountains, along the banks of Sandanska Bistritsa River.

The town has a convenient location, a mild to warm climate (with the highest average annual temperature in the country, +16°C) and relatively high concentration of thermal water springs, which all make it a popular destination for relaxation and recreation.

Sandanski has developed in an amphitheatrical fashion on the outer south-west flanks of Pirin Mountains along the lower reaches of Sandanska Bistritsa River.

Its geographical location between Kresna and Rupel Gorges determines the town's mild winter and unpleasant summer temperatures.

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.