Metallicity view of the IOM space for the PDR1-giants catalogue. The energy versus angular momentum in the z-direction is colour-coded by the PDR1 metallicities, with the Sun’s E-L_z shown as a red star (top centre). The energy versus z-angular momentum at different slices in metallicities is colour-coded by their density distributions with different substructures highlighted for PDR1 6D giants (bottom panels). The following acronyms are used in this figure: HTD, hot thick disc; Sgr, Sagittarius; GES, Gaia-Enceladus-Sausage; LMS-1, low-mass stream-1; MW, Milky Way.