The Pierre Auger Project is an international endeavour to study the cosmic ray spectrum at the extreme energy region starting at about 10(18) eV and reaching full efficiency at 10(19) eV. To definitely improve the statistical precision over the whole sky, the construction of two large Observatories in both hemispheres is envisaged. The Southern Observatory is under construction at Malargue, Argentina. In its final shape 1600 water-Cherenkov tanks will be deployed in an area of 3000 km(2). Also, 24 fluorescence telescopes will overlook the site from its periphery. During the prototyping phase, we proved that all subsystems behaved as expected. The full production proceeds now. (C) 2003 Elsevier B.V. All rights reserved.