In Precolumbian Central Mexico and the southern Andes, the Aztec and the Inca states created ritual landscapes that were based on observation of the natural environment and of celestial phenomena, but were also closely connected to cosmovision, defined as the structured view of nature and the universe in relation to man. By means of sophisticated architectural projects the landscape was transformed according to the canons of cosmological concepts, thus unifying time and space into a dialectical interacting whole. Simultaneously, the creation of these sanctuaries also expressed the exercise of power of these expanding states. I analyse several examples of the ritual landscapes created by the Aztecs in the Central Highlands and the Basin of Mexico, that are confronted with examples from the Incas in their immediate domain of influence around their capital, Cuzco. The comparative study of Aztecs and Incas may contribute to a broader understanding of Native American societies and landscape archaeology.