What is the second largest city in Bulgaria, after Sofia (its capital)?
Plovdiv
Ruse
Burgas
Varna
According to the 2011 census:  Plovdiv (338,153 inhabitants), Varna (334,870 inhabitants), Burgas (200,271 inhabitants) and Ruse (149,642 inhabitants)  
reach: rather globalBulgariacitiesEuropegeography
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Plovdiv
Ruse
Burgas
Varna
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