The Antonia Fortress that stood at the northwest corner of the Herodian Temple Mopunt had four towers, three of which were 50 cubits (86 ft./26.25 m) high and the fourth, the southeast tower, 70 cubits (120 ft./36.75 m) high. The view from this highest tower, that, according to Josephus “commanded a view of the whole area of the Temple” (War 5.242), must have been spectacular.
At the place where the northern and western porticoes met, there was a staircase leading up to the roof of the porticoes. At this place there was an entrance to the Antonia Fortress.
Here we can imagine the scene portrayed in Acts 21 and 22, when the Roman captain, Lysias, allowed Paul to address his fellow countrymen from the safety of the Antonia.