The Thickest Walls in the World
Once upon a time, when I ventured up to the Orkney Islands of Scotland (there are excellent standing stones and burial mounds there), I stayed overnight in a typical Stromness house, and they have walls four feet thick, due to the rough weather up there. That was impressive – a wall that should survive any hurricane.

(not a Stromness house, but is an ancient structure from the Orkneys)
Searching Google finds plenty of ancient constructions where walls are up to 5 metres thick – such as the Great Wall of China. The thickest walls of the Pentagon are three feet. Missile silos can have walls up to 14 feet thick.
But the thickest walls belong to structures that most don’t think of in terms of walls – the pyramids. Most people think of pyramids as giant, filled structures, typically with a few odd empty spaces inside. In reality a pyramid is a building with a few rooms, surrounded by walls up to 100 metres thick. When you look at pyramids in this way, then the question that needs to be asked is, why did they need such thick walls?
pyramids may require such thick walls just to provide strength , support to such large structure.
Or, massive walls require a large structure… If a pharaoh’s mission was to put 100 meters of stable rock between him and the sky (for protection from cosmic rays, or some other nasty that comes from space), perhaps a pyramid was the solution?
Time has shown how stable it is. And there’s never really been a good explanation for the size. Sure, big is important – grandeur for a leader. But a quarter as big would still be awesome, and easier to achieve.
Or, if you really want to understand it, ask why they didn’t build a bigger pyramid!
Hmm, your argument is quite strong . Just wondering where the kings so selfish, pyramids could hold only a handful of people during a catastrophe and the design has no windows or other provisions of fresh air.
Something else , I ve heard that the entrances of pyramids are located quite high is that true? If yes there are two possibilities one you need to have a prior knowledge of when the disaster is to occur and thus you need to get into pyramid early ,second it kind of makes it difficult for unwelcome guests or say common citizens to get into it.