Further on, I came upon four more ruined piles of bricks of this kind, all of them silent and deserted, and questions arose again. Who built them? When? And after the original city of Phan Na Tha Kan was abandoned when its inhabitants fled elsewhere, what was it about the old structures that kept the new Thai Lue villagers who moved in from disturbing or demolishing them? They could have used the land for farming, or to build houses.