125"Tech Cormaic and the Forradh, Tara." 3D Icons Ireland, The Discovery Programme, Et. Al., www.3dicons.ie/3d-content/sites/9-tech-cormac-the-forrad-tara.
This source describes the feature as a "...low mound with a small hollow in the middle which may be the foundations of a house or perhaps the outline of a small barrow."
Conor Newman describes the same feature: "The interior, some 816m2 in area, is relatively flat, apart from the outline of what may originally have been a rectangular structure, 5.5m east-west by 6m north-south, just east of centre. The fact that the remains appear to define a subrectangular internal space suggests that it may once have been a building or house platform with its long axis aligned roughly north-south. It did not register in the magnetometer survey of the interior..." (Newman, Conor. Tara: An Archaeological Survey. Dublin: Royal Irish Academy for the Discovery Programme, 1997, p. 83.)