OZCAR is a distributed national Research Infrastructure aiming at an integrated understanding of the Earth’s surface processes, from underground to the lower atmosphere, and from high mountains to coastal areas. OZCAR gathers instrumented sites, in France and overseas, realizing long-term observations of biological, chemical and physical parameters of groundwater, river water, glaciers, soils, and wetlands. OZCAR is an open community platform devoted to the auscultation of water and soil resources following an integrated scientific approach of terrestrial landscapes.