The Roman settlement overlooked a passage between the Hodna and the Sahara via the Aïn Rich plain and the valley of the Oued Chaïr, between the Ouled-Naïl and Zab mountains.
The Bad Ischl area has been inhabited since the time of the prehistoric Hallstatt culture. Documentary evidence of the settlement dates back to 1262, when it was referred to as Iselen.
Lugdunum, currently Lyon, France, was the capital of the Roman province of Gallia Lugdunensis. The city was founded in 43 BC by Lucius Munatius Plancus. Two emperors, Claudius and Caracalla, were born in Lugdunum.