Two completely vanished environments in Greece, a shallow coastal bay at Dimini near Volos and a large freshwater lake near Lerna south of Argos, were found and reconstructed with over 200 auger and drill cores. Similarities between the coastal landscapes of modern Volos and Argos with respect to topography and settlement history are attributable to comparable geological settings and Holocene environmental histories; for example, at both places active faulting has played a significant role and shoreline shifts have determined site locations. Near Volos the sea extended 3 km farther inland during the middle Holocene, reaching the base of Dimini Magoula (tell). After the Neolithic the shore gradually receded, resulting in a seaward shift of settlements, thus explaining the presence of several single component sites in the area. Near Argos, the former presence of a large freshwater lagoon, named Lake Lerna, has been deduced from subsurface deposits. The lake was separated from the open sea by a beach barrier. It originated when the postglacial sea level rise reached its culmination point and extended over a diameter of 4.7 km in the Early Bronze Age. Increased soil erosion then caused a rapid silting, but remnants of Lake Lerna persisted until the last century. Anthropological studies have shown how the inhabitants of this coastal marsh have suffered from malaria in the past. It may be that the story of the legendary fight between Herakles and the Lernaean Hydra reflects the struggle of the Lanai people as they tried to change the inhospitable environment by draining the lake.