The sheets of the Geological Atlas of Switzerland give detailed information on the uppermost layers of sediment and bedrock. Geological formations are represented by colours, conventional signs and symbols, in accordance with their age, composition and tectonic structure. The topographic background of the series in preparation is provided by the Swiss National Map at 1:25,000 scale. For each sheet, an explanatory booklet is also published, in which the geological formations and special features of the area in question are described. An indispensable tool for geologists, engineers, planners, government departments, scientists and schools.