During the period of Late, Neolithic-Early Bronze Age was a change in culture and climate resulted in wetter and cooler temperature in conjunction with a dramatic sea level rise.
The rising sea flooded or cut areas of land changing the landmass we see today. The impact on agricultural areas, routeways, and sites of occupation transpired in loss of food resource from coast edges, altering the whole ecosystem and having an effect on wildlife both on land and in the sea.
The landscape you see today is significantly changed for example the area around Callanish complex I will describe the changes and help to put you back into the Neolithic landscape.
The majority of Neolithic stone circles/stone setting sites are set in the landscape to be intervisible, viewed from a great distance and mainly located near to the coast, consequently helping as a navigation aid on land and more importantly at sea.
Bronze Age sites are mainly single standing stones and 80% are less than 1Km from modern coastline.