Note 050
There are three topographical points which indicate the situation of the palace. 1. The staircase which connected it with the Hippodrome or Atmeidan. 2. A small artificial port on the Propontis, from whence there was an easy ascent, by a flight of marble steps, to the gardens of the palace. 3. The Augusteum was a spacious court, one side of which was occupied by the front of the palace, and another by the church of St. Sophia.
Note to Chapter 17 of Decline and Fall by Gibbon