Many of the finest artefacts from the Bronze Age in the Mälar/Hjälmar landscapes have not been found at settlements or in graves, but at sacrificial sites. They are often located in wetlands: as a rule, the objects have come to light when people have drained bogs for cultivation or dredged rivers. There are exquisite bronze weapons, jewelry and tools and carefully crafted stone axes. Archaeologists have hardly ever been involved until the finds reach the museums. On the whole, archaeologists in the area have done very little wetland excavation, probably because it is so heavily forested that there has never been any significant peat extraction. The aim of this project is to get to grips with the sacrificial sites, which nobody has done anything with for a very long time. The main objective is to examine the pattern of where already known sacrificial sites are located in the landscape and establish a model for where field archaeologists can expect to find them. Wetlands offer exceptional preservation conditions where you have the chance to find things that are not found in any other environment. In the case of the sacrificial finds, we are also dealing with practices that did not take place elsewhere. In both these respects, the project has the opportunity to produce completely new knowledge about Bronze Age society in the Mälar/Hjälmar landscapes.