Ophel - (Easton's Bible Dictionary)
Hill; mound, the long, narrow, rounded promontory on the southern slope of the temple hill, between the Tyropoeon and the Kedron valley (2 Chr. 27:3; 33:14; Neh. 3:26, 27). It was surrounded by a separate wall, and was occupied by the Nethinim after the Captivity. This wall has been discovered by the engineers of the Palestine Exploration Fund at the south-eastern angle of the temple area. It is 4 feet below the present surface. In 2 Kings 5:24 this word is translated "tower" (R.V., "hill"), denoting probably some eminence near Elisha's house.