One example of our astronomical heritage

One of the 177 Antas, a distinctive form of megalithic tomb, found in the central part of the Alentejo region, Portugal, and in the provinces of Badajoz and Cáceres, in the Extremadura region, Spain. These tombs are thought to have been constructed from c. 4000 BC onwards. The range of orientations of the 177 monuments corresponds almost exactly to the range of possible rising positions of the Sun.