In my work the alleged start of the Pharaonic Egyptian, Hindu (Vedic) and Maya calendar(s) is December 25, 3117 BC.
That date is based on many years of analysis of Pharaonic
Egpytian dynasties and other sources - e.g. Sumerian artifacts, or the Maya
and Hindu calendars, etc., which are currently and erroneously
thought to start in 3114 BC and 3012 BC respectively - see e.g.
http://webexhibits.org/calendars/calendar-mayan.html
http://www.vedicsky.com/KeyFeatures.pdf
http://webexhibits.org/calendars/calendar-ancient.html
as well as on the basis of a study of solar eclipses and on the way
the megaliths mark the sky at megalithic sties. Due to precession,
the sky "moves" - as seen from the earth - in a cycle of ca. 26,000
years, so that the positions of the solstices and equinoxes in the
sky of stars (as marked e.g. on the megaliths) also move. If a
solstice or equinox is marked on an ancient stone as taking place
within a given constellation, the date can be computed. There is a
lot of information at http://www.megaliths.net on this but for the
calendar in particular see:
http://www.lexiline.com/lexiline/lexi20.htm
http://www.lexiline.com/lexiline/lexi760.htm
http://www.lexiline.com/lexiline/lexi18.htm
http://www.lexiline.com/lexiline/lexi768.htm
http://www.lexiline.com/lexiline/lexi762.htm
http://www.lexiline.com/lexiline/lexi75.htm
http://www.lexiline.com/lexiline/lexi203.htm
http://www.lexiline.com/lexiline/lexi78.htm
http://www.lexiline.com/lexiline/lexi102.htm
http://www.lexiline.com/lexiline/lexi11.htm
http://www.lexiline.com/lexiline/lexi69.htm
This is complicated stuff. For now, my analysis must be considered
very speculative, until or unless it is confirmed down the road by
other researchers. The Maya scholars do not budge from their August
3114 BC date, but as I show at
http://www.lexiline.com/lexiline/lexi75.htm
they are clearly in error.