Fish have constituted an essential part of subsistence and diet among prehistoric foragers and the even later farming populations of Fennoscandia. Northern hunter-fisher-gatherers have often adapted their site location strategies to maximise fishing at favourable fishery locations, such as river estuaries, coastal areas and inland lakes. Changes in the settlement patterns of the fourth millennium BCE estuary populations of coastal northern Ostrobothnia, northwest Finland, have been seen as reflecting increased social communality. This also allowed joint initiatives in resource procurement, for instance, mass fishing with stationary wooden structures, which have been found in abundance in waterlogged conditions in the area. Riverbank housepit villages, especially the ones located by the rapids and islands, may be assumed to have been associated with the mass-harvesting and/or processing locations of seasonally and spatially aggregated fish resources. During the early Neolithic, the settlement pattern of the lake populations of southern Finland may be suggested to have been mobile and periodic, and the economy related to seasonally abundant lake resources, freshwater fish (e.g. pike and cyprinids) and nutrient-rich plants (water chestnut and hazel) in particular. Wooden stationary structures were frequently used in lake fishing practises and, through time, more permanent habitation at profitable fishing grounds increased. More active and long-term use of lake settlements in the northeast Baltic, starting in the mid-fifth millennium BCE, may be linked to the economic shift towards a more intensive utilisation of freshwater resources, as has been observed at waterlogged lake sites with good preservation of organic materials.