Recent research into Pre-Roman Iron Age and Roman Iron Age peat reclamations in Friesland has made clear that the margins of the peat area were intensively inhabited during both periods. This same research also provided insights into the local environmental circumstances under which the settlements were founded, the shapes these settlements took, and the way they functioned in a changing landscape. Although growing problems with peat subsidence, which increased the local water table, eventually forced the settlers to leave their settlements and settle on newly reclaimed peat land, this did not necessarily mean the end for the old sites. The old reclamations silted up, which raised the land surface and reversed the effect of the subsidence, thereby, in time, making the old reclamations once again attractive for habitation. In the Late Roman Iron Age all reclaimed areas were abandoned, as were most of the salt marshes.