Judges 9:51

But there was a strong tower within the city
The tower of Shechem was without the city, but this within, as towers generally are:

and hither fled all the men and women, and all they of the city;
men, women, and children, man and maid servants, all the inhabitants of the city; the tower being a large place, having not only many rooms in it, but perhaps a large area in the midst of it, as well as it had battlements on the top of it:

and shut it to them;
the gates of it, and which no doubt they strongly barred and bolted, to keep out the enemy:

and gat them up to the top of the tower;
to observe the motions of Abimelech, and annoy him as much as they could with what they carried with them, as stones, and the like.