Mapping of glacial landforms using lidar data shows that the retreating margin of the Fennoscandian Ice Sheet dammed a series of lakes in the Torneträsk Basin during deglaciation. These lakes were more extensive than previously thought and produced outburst floods. We show that sections of the Pärvie Fault, the longest glacially activated fault of Sweden, ruptured multiple times and during the existence of ice-dammed lake Torneträsk.