Upper panels: CMD of VV124 from the ACS data within (left panel) and outside (right panel) a circle of radius R_p = 40″. The average photometric errors are reported as error bars in the left panel. Lower panels: CMDs in other regions of the ACS field delimited by the ellipses plotted in Fig. 1. The right panel regards a radial region similar to that considered in Paper I to tentatively detect the extended HB population (see their Fig. 9). In all the panels stars are plotted as black points in regions of the CMD with a few stars and as gray squares otherwise, with the scale of gray proportional to the local density of stars in the CMD (lighter tones of gray correspond to higher density).