Upper left panel: the adopted selection boxes are plotted on the CMD for r_ϵ > 0.5′ (the innermost region has been excluded to avoid confusion in the panel). Upper right panel: a synthetic HB population computed from BASTI models, reported to the same distance and reddening of VV124, is superposed to the observed CMD for r_ϵ > 1.5′. The radial selection is adopted to obtain the cleanest view of the HB. Red HB, RR Lyrae variables, and blue HB are plotted in red, green, and blue, respectively. Lower panel: radial distribution of the various populations selected with the CMD boxes, as indicated by the labels.