From Paul Gosling on researchgate (researchgate.net/figure/Photograph-dated-c-1920-of-the-barrow-group-on-the-summit-of-Slanemore-Hill-Co_fig6_325011589) in reference to the black and white image:
“Photograph dated c. 1920 of the barrow group on the summit of Slanemore Hill, Co. Westmeath, 6.5km north-west of Mullingar (Source: Shaw 1921, pl. xxii). The view is from the north and shows three of the five barrows on the hill-from right to left these are RMP WM018-078002, WM018-078001 and WM018-078. In TBC I, Mac Roth, the messenger of Medb and Ailill, describes the arrival of the Ulaid forces here as follows: ‘There came on to the hill at Slemain Mide … a great company, fierce, powerful, proud. I think that it numbered three thousand. At once they cast off their garments and dug up a turfy mound as a seat for their leader’ (lines 3589-3592 and p. 221). ”