Describe or post a screen capture of the entrance to your fort. From the outside through and down to the main actual start of your fort. Do you dig down to the stone? do you channel or use stairs? Do you have an outer entrance and an inner entrance?
I'd like to know
I'm on a cliffside embark. I have an entrance at the top of the mountain, or what is now the top after I got rid of the actual top. I also have an entrance at the bottom to the trade depot, unconnected to the rest of the fort, with space for a drawbridge to close it off. I also have another entrance next to the trade depot, but I have left walls keeping it closed off for now.
Eventually, I will close off the top entrance and put fortifications there, and build a mini-tower over it to turn into an entrance I can open and close.
Then, I will turn the trade depot into a sort of airlock, so I can open it to caravans while keeping the rest of the fortress closed, and when the caravan goes, close it off again and open the depot to the fort, so I can move any important items inside. Similarly, I will have another airlock for the alternate entrance, which will mostly remain closed.
In the instance of invasion, I will close the bottom entrances and open the inconvenient, nearly useless tower "entrance" to cause invaders to try to path in that way, where they will be showered with arrows through fortifications both from the fortress itself and the mini-tower.
This is what it looks like now, though.
The security is absolutely terrible, with human visitors and bards and the like wandering in and mingling with citizens right in our main barracks.
And here's the trade depot "entrance" and the parallel entrance.
The parallel entrance is going to be closed off entirely, although it may be replaced with a maze of death traps instead. Probably closed off, then I'll get around to the traps later.