Coastal ridges that represent former coastal barriers and beach ridges, are widely distrib-uted among the lowlands of the Japanese Islands. The distribution of archaeological sites in the coastal lowlands indicates that these coastal ridges have been important landforms for human activities.  Relationships between Holocene geomorphological development and human activity in the regions are clarified from a study of three sites along Suruga Bay in central Japan where typical coastal ridge landforms are recognized and on which archaeological sites dating from ca.3,000 BP are also widely distributed.  The time lag between when enclosure of the lagoons behind the coastal ridges and human settlement is calibrated. It was often thousands of years after the final stages of their formation before humans began to advance and settle on the coastal ridges because it took several thousand years for the coastal ridges to become stabilized and to be free from the influence of seawater.