13 historic monuments, puzzles which are still not solved

Stonehenge, England

According to the epic, the stone complex erected magician Merlin. In fact, Stonehenge appeared long before the time of King Arthur hypothetical life partner. But as people were transported very heavy boulders from the quarry, found hundreds of kilometers away? It is not clear, and construction purpose: whether it was the observatory (the location of megaliths – the exact model of the solar system), or the sanctuary (in that it was used as the priests of the Celts – Druids).