>the basics were nothing of the sort at the time
Yes. And of course, "at the time" was also nothing of the sort. The 8th century was not the 14th. As obvious as that sounds, when one says "medieval castle" there's a type that springs to mind, and it's pretty much northern French and Britain, mostly 14thc-15thc. And much of that has more to do with what has happened to survive than it does with common practice or superiority of design.
It's probably also worth mentioning that for about half the Middle Ages, "castles" were made of wood. It's worth saying, further, that a good many stone castles were basically just square towers three or four stories tall with no entry at ground level.
Yes. And of course, "at the time" was also nothing of the sort. The 8th century was not the 14th. As obvious as that sounds, when one says "medieval castle" there's a type that springs to mind, and it's pretty much northern French and Britain, mostly 14thc-15thc. And much of that has more to do with what has happened to survive than it does with common practice or superiority of design.
It's probably also worth mentioning that for about half the Middle Ages, "castles" were made of wood. It's worth saying, further, that a good many stone castles were basically just square towers three or four stories tall with no entry at ground level.