In order to align their monuments with celestial bodies, ancient societies sometimes utilized local elevation points to help them track and record celestial movements. In this way they fixed a point in the sky with objects on the ground. Usually hilltops, valley depressions or mountains served as horizon points.

The nasca lines in Peru have long tracks made of stone clusters etched out on the ground. These tracks travel in straight lines for miles and miles even over any obstacles such as mountains. They have generally been accepted as pointing to rising constellations over the Atacama desert.

The summer and winter Solstice points measured respectively longest day/shortest night and shortest daylight time. If these were accurately calculated, the society, frequently agrian in nature, guaranteed maximum sowing and harvest times year after year, weather permitting,of course.

Following the sun and moon's movements across the skies could denote Solstice times and Spring and Autumn Equinoxes (periods in between solstices) to give 4 even measurements. over a yearly cycle.