The castle began as a tower in a line of connected defensive structures.

这座城堡最初是一排相连的防御建筑中的一个塔。

This is typically what is found inside of broch, rather than what some people would expect with a defensive looking structure.

这是一般会在 broch 内部发现的东西，而不是一些人所想的具有防御性结构的东西。