  I discuss various aspects of archeoastronomy concentrating on physical
artifacts (i.e., not including ethno-archeoastronomy) focusing on the period
that ended about 2000 years ago. I present examples of artifacts interpreted as
showing the interest of humankind in understanding celestial phenomena and
using these to synchronize calendars and predict future celestial and
terrestrial events. I stress the difficulty of identifying with a high degree
of confidence that these artifacts do indeed pertain to astronomy and caution
against the over-interpretation of the finds as definite evidence.
  With these in mind, I point to artifacts that seem to indicate a human
fascination with megalithic stone circles and megalithic alignments starting
from at least 11000 BCE, and to other items presented as evidence for Neolithic
astronomical interests dating to even 20000 BCE or even before. I discuss the
geographical and temporal spread of megalithic sites associated with
astronomical interpretations searching for synchronicity or for a possible
single point of origin.
  A survey of a variety of artifacts indicates that the astronomical
development in antiquity did not happen simultaneously at different locations,
but may be traced to megalithic stone circles and other megalithic structures
with possible astronomical connections originating in the Middle East,
specifically in the Fertile Crescent area. The effort of ancient societies to
erect these astronomical megalithic sites and to maintain a corpus of astronomy
experts does not appear excessive.
