The site was abandoned sometime during the Late Neolithic to be reoccupied in the Early Bronze Age (from ca. 2500 B.C.) when it flourished. It was then fortified and included a large, rectangular building named the "House of Tiles" because of the numerous clay roof-tiles found in its debris during the excavation. In one of its rooms, lumps of clay bearing seal impressions were discovered. The sealings and the remaining artefacts imply maritime communications and trade with other regions of the Aegean. This building as well as the fortifications were destroyed before the end of the Early Bronze Age (ca. 2200 B.C.). The settlement continued to be inhabited in the Middle Bronze Age (until about 1700 B.C.) but during most of the Mycenaean period (1800-1250 B.C.) the mound was used mainly as a cemetery and only sporadically for habitation. In about 1250 B.C., the site of Lerna was definitely abandoned.