Pirdop (Bulgarian: Пирдоп [pirˈdɔp]) is a town located in central-west Bulgaria in Pirdop Municipality of Sofia Province in the southeastern part of the Zlatitsa–Pirdop Valley at 670 m above sea level.

[1] It is surrounded by the Balkan Mountains (also known as Stara Planina) to the north, Sredna Gora mountain range to the south, and Koznitsa and Galabets saddles to the east and west, respectively.

The Pirdop copper smelter and refinery is the biggest in the Balkans and whole of South-Eastern Europe.

The factory also produces 830,000 tons of sulphuric acid and employs 1,420 workers.

The main chimney of the factory is 325 metres tall and shares together with the chimneys of Maritza East Power Stations the title of tallest man-made objects of Bulgaria.