Banja Luka or Banjaluka is the second largest city in Bosnia and Herzegovina, and the most populous in Republika Srpska. It is Republika Srpska's main economic, political, and administrative center. Banja Luka is the traditional centre of the densely forested Bosanska Krajina region of northwestern Bosnia and Herzegovina. According to the 2013 census, the city proper has a population of 138,963, w…