Flavius Josephus locates the place of John the Baptist’s confinement and execution at Machaerus (Antiquitates Judaicae XVIII 5,2). The fact of John’s imprisonment is attested by all the Gospels, and their accounts are consistent with and complement that of Josephus. The intention of the author is to situate the archaeological site in its New Testament context, in order to elucidate the blurred scene of a biblical site, and reconstruct it as clearly as possible in the light of 21st century historical, archaeological and architectural research.