It's bunk. When I came across this supposed fact, it gave me pause. If indeed it were true, it meant the person who chose the location of the pyramid knew about the geography of the earth. It would be an unlikely coincidence for the pyramid to be on either of these lines. I assume it is there because it is a place near the civilization. Today, Cairo comes almost to the base of the pyramid.
But in reality the great pyramid does not lie on ether line of most land.
http://www.catchpenny.org/pyramid.html "If by "meridian" Smyth [someone making the claim] means a half-circle, then the claim's accuracy may still be disputed (it is entirely anecdotal and no mathematical proof has been offered). It appears that a meridian a few degrees to the west (in blue below) would cross more land."
and
" Again, this is doubtful. A line of latitude several degrees north (in orange above) traverses more land."

A number of other myths are explained:
http://forum.grasscity.com/science-n...-answered.html

People just like to believe.

~~ Nehmo