Aïn Defla (Things to do - Places to Visit) - AIN DEFLA Top Tourist Placesbr City in Algeriabr Aïn Defla is the capital city of Aïn Defla Province, Algeria. It is also a commune. In Roman times the city was called Oppidum Novum. The vestiges of the Oppidum Novum are still visible.br br The current city was founded in the 20th century by a soldier named Ahmed Mahmoudi of the rank of agha, with the idea of bringing together the indigenous populations from the villages of the region.