The flag of the City of Banja Luka consists of the "Kastel" fortress on a red background, under which is located the Vrbas river, represented in blue and white waves, in which the tips of two "kajak" boats can be seen in blue.
Ivan_VA - Predlog grba Grada Banja Luka, Grad Banja Luka, CC BY 4.0, <a class="external free" href="https://sr.wikipedia.org/w/index.php?curid=1991028">https://sr.wikipedia.org/w/index.php?curid=1991028</a>
CC BY 4.0
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