Great work as always @tremendospercy I have to admit although I was aware of the spheres I have yet to actively research them so this post provided a wealth of information. Like yourself I'm really unsure as to what they were used for? equally I feel that they must have had some kind of purpose. Perhaps some way of mapping a scale model, circumference of the world? A way of marking certain sites? I don't know and I'm clutching at straws and scratching my head! This one has me stumped and I usually have a few ideas! One things for sure I'm certainly going to pay closer attention to these discoveries over the next few years and see if anyone comes up with some more plausable explanations. Great post!!