What do megaliths imply about the northern European civilization that built them?

Megaliths imply a high level of social organization and engineering skill in the northern European civilization that built them. The construction of these massive structures required the cooperation of large numbers of people, and the transportation and erection of the stones required considerable technological expertise. Megaliths also suggest that this civilization had a strong religious or spiritual belief system, as many of these structures were used for ceremonial purposes. Finally, the megaliths indicate that this civilization had a long and stable history, as many of these structures have been dated to the Neolithic period, which began around 10,000 BC.