The Pierre Auger Observatory, based in Mendoza province, Argentina represents the largest ultrahigh-energy cosmic ray observatory ever built. After twelve years of operation the exposure reached almost 60 000 km2 sr yr and the unprecedented quality data set spans three orders of magnitude in energy. The status and performance of the detectors and their enhancements are described. The rich harvest of the results obtained so far is presented including the energy spectrum, searches for anisotropy, measurement of the position of shower maximum and their interpretation in terms of mass composition as well as limits on photons and neutrinos in the primary flux. Implications of the results on future operation and motivations for the upgrade of the Observatory are also discussed.