Complex sentence: The mound was a scene of settlement in a continuous sequence of development from the Chalcolithic Age, when earliest copper tools appeared alongside the use of stone tools; it has been continuously occupied ever since, today's settlement being a small village.
Split into simpler sentences: The mound was a scene of settlement in a continuous sequence of development from the Chalcolithic Age, when earliest copper tools appeared alongside the use of stone tools. It has been continuously occupied ever since, until today's modern settlement in the form of a small village.