Plovdiv is the second-largest city in Bulgaria after the capital Sofia, with a population of 341,567. Plovdiv is situated in south-central Bulgaria on the two banks of the Maritsa River. The city has historically developed on seven syenite hills, some of which are 250 m (820.21 ft) high. Because of these hills, Plovdiv is often referred to in Bulgaria as "The City of the Seven Hills".
Plovdiv has one of the country's fastest-growing economies with average GDP growth of 12%–13%. Industry has been rapidly expanding since the late 1990s, with manufacturing plants built in the city or in its outskirts, mainly the municipality of Maritsa. In this period, some €500 million were invested in construction of new factories. Some of the new plants include the Liebherr refrigerator plant with 1,850 employees and a capacity of 450,000 items per year, the Socotab tobacco processing plant (2,000 employees), a bicycle plant (500 workers, capacity 500,000 units), а Schneider electronics factory, a biodiesel plant, the Bulsaphil textile plant (790 workers), and several electronics and high-tech plants producing CD players and other electronic equipment. The largest electronics plant in the Balkans was inaugurated in the nearby village of Voivodinovo.