Introduction: the microscopic record in archaeology. Micromorphology of thin sections: history, undisturbed samples, sampling and preparation, the polarizing microscope. The thin sections description of soils and archaeological deposits: descriptive criteria and basic concepts (fabric, microstructure, mineral and organic constituents, groundmass, C / F ratio, pedofeatures). The micromorphology for palaeoenvironmental reconstruction: the frost features, the coarse illuviation, the onset of dry conditions, the formation of calcareous crusts, the relict features. The micromorphology as geoarchaeological tool: features related to land use and to activities in settlement sites (pastoralism, hearths, floors, urban areas). Study cases.