[@Cyclone]I was more thinking about pouring blood into the pit, burning bonfires around the edge, building ziggurats around them, laying the dead outside it tower of silence style:
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[img]http://img.photobucket.com/albums/v661/supine/blogstuff/towerofsilence_interior550.jpg[/img]
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I'm not sure where the wells would [i]lead[/i]. Does a labyrinth of sewer-like tunnels filled with all the gore and offerings made to the wells sound like a good idea? It'd be full of the burrowing centi-snakes that made it, but it could function as a surreptitious mode of transport for the very brave.

I don't know much about native American culture. Europe/Africa/Asia's more my thing.