Haltherrion
First Post
This raises alot of points. How common of a threat is a mid-level adventuring party?
This is just meant to raise a thought exercise: test the likely garrison (as you see it; I see no reason to stick to one person's thoughts on the garrison of a castle, i.e. Gygaxian) against your own players as a raiding party and see how that castle fares.
I think picking a small size garrison is interesting because there are clear historical precedents in Wales regarding some of the very castles likely to come to mind when people think of castle but you can choose your own antecedents. And one could easily imagine a mid-level group of freedom fighting Welsh adventurers trying to take the place.
One could make a case that for hardened veterans, at least some of them are higher than level 3 but nonetheless, it seems a small garrison is probably almost entirely fighter-type, maybe a few rogue-type which leaves them vulnerable to the typical adventuring party that is an effective combined arms fighting group of range, melee, control and healing. Of course, you also get into game mechanic issues where the games are tuned so that higher level folks can smash lower level folks perhaps more readily than they can in real life. (Was the crossbowman who killed King Richard level 3 or level 9?

My wife and I have been rewatching the Rome HBO mini-series. While the show takes many liberties it probably isn't too far off in the "feel" of things. It was a reminder that the rank and file might be fairly tough folks. One would certainly peg Vorenus and Pullo as very high level warriors. Vorenus was high rank so maybe he is uncommon but Pullo wasn't ranked. A 10-20 year Roman legionnaire in a period and place where he saw a lot of combat might be fairly high level in D&D in terms. On the otherhand, D&D would peg Vorenus as a captain since he was first centurion and in D&D terms captains span a large number of men and aren't common. But even so, perhaps the standard level distributions in a seasoned army are too low in most D&D sources. Not that I tend to use them myself.
We also haven't addressed the strategy of castle buildnig.
There is much we haven't addressed. But in the absence of a defined baseline, it is useful to offer historical analogs to at least remind folks how castles were used in an Earth setting.
That is the key questions we are trying to answer. What are the alternatives to castle construction?
Indeed it is

In this sort of endeavour, if folks could approach it in good spirit, it might be interesting for a few interested in this topic to state their assumptions and then describe how they see fortifications evolving given those assumptions. It's as good a method as any and at least requires someone to declare their assumptions.