The River and the Sky: Astronomy and Topography in Caral Society, America's First Urban Centers

America's first urban centres were allegedly located at the Supe Valley sites in Peru. After investigating location and orientation of main built structures, we show that it is not only presence River determines their but also astronomical relationships within buildings dictate setting valley. The southernmost position moonrise on horizon seems to be most important target. There possibility an evolution toward attributing greater importance June solstice sunrise rising certain stars or asterisms. These orientations could elate specific moments throughout year, particular seasonal rains, subsequent river flooding, agricultural cycles. This one earliest examples interaction land- skyscapes human cultures indeed Americas.