Wetlands constitute remarkable natural archives of environmental history. The wetlands best suited to palaeoenvironmental studies are peat bogs and lakes, thanks to both local anoxic conditions and sedimentary accumulation that is often highly organic and, above all, undisturbed over time. This represents favourable local conditions for the conservation of bioindicators of the past environment. In this sense, pollen grains have been used for many years to reconstruct the history of vegetation and its evolution in relation to natural and anthropogenic forcing. Other bioindicators are rich in information about the history of past environmental conditions, be there studied in the same times of pollen analyses, such as the so-called non-pollen palynomorphs (NPPs) which are fungal, algal or micro-faunal remains (e.g. Marret et al. 2021), or studied by mean of specifics technical studies such as diatoms, chironomids. The wetlands allowed then to reconstruct past climate and land uses, and provide useful information about water through time: palaeohydrology, water level, trophic status of water bodies… These are all parameters that must have been considered by past societies and on which their development must have had an impact in return. In the archaeological sites, the presence of wetland is rare and concerns only some specific kind of habitat such as lake dwellings for example. However, the sedimentary infilling of structures related to water management: water supply/management structures such as canalisations, basins, wells, ditches… can provide useful information at the heart of human settlements. Finally, the presentation will present the first paleaoenvironmental investigations performed around the site of Justiniana Prima - Caričin Grad (e.g. Ivanišavič 2017) that were conducted in October 2023 in collaboration between the EFR, the Archaeological Institute of Belgrade (Serbia) and the Chrono-environnement Lab. from Besançon (France).