It may be a coincidence, but if you multiply the height of maen llia(12.6ft) by 38, it comes out at the same as the height of the great pyramid at giza.(480FT)The angle of the north facing slope of maen llia is 38 degrees.

If you divide 480 by 51.84(decimal for 51deg51min) it comes out at 9.26, which is the width in feet of maen llia from north to south.

The angle of the slope of the sides of the great pyramid is 51deg and 51 min's, the same as the latitude of maen llia( and the same as the south facing slope)

According to the team investigating the area around stonehenge( time team special on tv just lately ) the Alter stone may not have come from Milford Haven as originally thought, but could have come from the Senni beds of the brecon beacons. The Senni valley is a few hundred meters north of Maen llia.

This could have been written by Dan Brown. Tune in for more instalments, coming soon.