Families and households were still largely independent economically, and the household was probably the center of life. However, excavations in Central Europe have revealed that early Neolithic Linear Ceramic cultures ("Linearbandkeramik") were building large arrangements of circular ditches between 4800 BC and 4600 BC. These structures (and their later counterparts such as causewayed enclosures, burial mounds, and henge) required considerable time and labour to construct, which suggests that some influential individuals were able to organise and direct human labour — though non-hierarchical and voluntary work remain possibilities.