Hrvatska Kostajnica (pronounced [xř̩ʋaːtskaː kǒstaːjnit͡sa]; German: Castanowitz; Italian: Costainizza), also referred to as simply Kostajnica, is a town in central Croatia. It is located on the Una river in the Sisak-Moslavina County, south of Petrinja and Sisak and across the river from Kostajnica in Bosnia and Herzegovina. In the past, Hrvatska Kostajnica was called by different names, Koztainicha, Kaztanicha to Costgnanica. The name most likely comes from the word Kostanj (chestnut).
