facts of The Great pyramid in giza

1.It also called Pyramid of Khufu.
2.There are pyramids for Khufu's son and grandson next to Khufu's pyramid.
3.There is a sphinx near the The Great pyramid.
4.It is an one of the 7 mysteries
5.It was the highest building in the world for 3800 years.
6.Average stone that is used for The Great pyramid was 2.5 tons.
7.Actually, there was a gold at the top of this pyramid.
8.It has a mystery that there is no dead pharaoh in the pyramid and there is no treasures in there when 7th Kalif (leader in Islam) just went there.
9.There are 3 secret room in this pyramid.
10.It built up like BC2500