Ophel, the southern spur of the temple hill, having a wall of its own Nehemiah 3:27 might be reckoned either in Jerusalem or outside it. Here it is made a separate place.
SDA Bible Commentary (limited)
Volume 1-7
21. The Nethinims. On the Nethinims, see on Ezra 2:43; for those who lived on Ophel, see Neh. 3:26.