Islam-aga's Mosque
Niš, Serbia · built 1870
Islam-aga Mosque (Serbian, Islam-agina džamija) is the only working mosque in Niš, Serbia. There is another in Niš Fortress which is converted into a gallery, and another close to the University Rectorate, that was damaged during the Anglo-American bombing of the city in 1944. It was built in 1720 and reconstructed in 1870. Of the twenty mosques in Niš during Ottoman rule, it is the only one that remains in use. It was torched during riots in 2004, and reconstructed in 2013.
Mosque data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).