Following paper deals with the questions about prehistorian and medieval settlements in the Mälar Valley and their relations to the historically known hamlets or single farmsteads from the 17th- and 18th-century cadastral maps. Models over settlement development through the period A.D 200 to 1700 done by geographers Ulf Sporrong and Dan Carlsson are tested and compared to the knowledge won by recent archaeological excavations. Is there a connection between the older settlements linked together by dry-stone walls and the late Iron Age settlements? Does the picture differ from the one presented for the Gotland region? How well are the general theories about different settlement development depending on basic natural conditions as for the potentials for cultivation and topography, corresponding to the physical remains?  Are there other factors involved when the settlement structure takes its form?The methods that are used here constitutes mainly of a comparison between different locations in the Mälar Valley that has got a well known prehistory thanks to extensive archaeological excavations. Cadastral maps, soilmaps, topography maps and maps over ancient monuments are intertwined to the same map and analyzed through works in Geographical information systems.The results of this study reveal an interesting suspicion in the continuity-question through the Iron Age.