No real volcanoes in the area, they had to have some place to throw the occasional virgin...
Probably more true than you may have intended. There are other places, too. Huaca Prieta. While not a "volcano" type mound it is very old. As could be this one. These people were big on ceremony. This mound, in its original state, could very well have been a man-made ceremonial lake.
There is another man-made ceremonial lake down there, but I can't remember the name of it.
As far as I can tell, there has been site appropriation all over the world. Later cultures building onto older structures and claiming it all as their own construction. There is much evidence of it in the ME, as well as South America. Actually, all over the planet. What I find very interesting is the better work, the highest technologically, is the oldest. And there is something about that fact that fills me with great sadness.
