  The heartland of the Khmer empire is literally crowded by magnificent
monuments built in the course of many centuries. These monuments include the
world-famous state-temples, such as Angkor Wat, but also many other temples and
huge water reservoirs. Using Google Earth data as well as GIS data and
reconstructing the ancient sky with Stellarium, we investigate here on the
relationships of astronomy with orientation and topography in a systematic
fashion, following the methods of modern Archaeoastronomy and strictly keeping
at a bay vague or esoteric proposals put forward by many authors in the past.
As a result, a very clear pattern of cardinal orientation and alignment arises,
connected with the temple's symbolism and the management of power by the Khmer
kings. As a bonus, the comparison with the Angkor monuments allows to put
forward a explanation for the anomalous orientation of the unique two
peripheral state temples of Cambodia.
