What is the maximum strength/size of infantry units that may defend a besieged wall

This saturday we tried a siege as a test scenario in which Twilight Kin and Ratkin defended the town walls against a united Goblin and Orcs attack.

It is understandable that towers can only be defended/occupied by individuals, troops and siege weapons and weapon teams. But is it correct to say that there is no limit to the size of the infantry that can defend a wall section?

The other question arises about the maximum size of an attacking unit trying to capture towers or wall sections.

Do you mean the siege rules in the last 2nd edition Clash of Kings?
May have been the one before, no matter.

I recall so, yes. Don’t recall a limit.

Either way, the siege rules are meant to be casual: so adapt as makes sense to you.

It just states “up to on Infantry or Large Infantry unit” can garrison a section, with the additional restriction on what can garrison a tower.

Since you can only attack a tower from a wall there is no additional restriction on unit size

The rules are a bit badly written on that section but having played a number of sieges here’s how we do it

  1. Wall sections are 12 inches
  2. Each can be garrisoned by a single infantry / large infantry unit of any size (Troop - Legion)
  3. Each can only be attacked by a single attacker - key otherwise there is no way a defender will win with a 12" length to attack.
  4. For the wall section containing the gate a 2nd unit may attack that

you don’t even need houserules…
page 10 states:
Up to one Infantry or Large Infantry unit
(including Individuals) may occupy each
section and is considered as “Garrisoning”.

in 3rd ed this means you could garrison with infantry, heavy infantry, ranged infantry, large infantry, or monstrous infantry. but not cavalry, chariots, monsters or war engines.
not sure where swarms fall on this. (at a guess alongside monstrous infantry.)

and as far as the rules go i’m not seeing any limitation on how many enemies can attack a wall. the only specification is that they have to attack the wall itself, not the unit garrisoning it, unless they meet special criteria.
Charges may be declared against a castle
wall section or gate from either side of the
castle wall, as if it were an ordinary unit.
A charging unit must make contact with a
wall section if they intend to attack a unit
Garrisoning it.

the big thing is this one:
A Garrisoning unit may only be attacked
from the outside of the castle if the
attacking unit has Siege Equipment that
allows it to, or it is of Height 4 or more

though i agree that a 12" frontage makes it really hard to defend with only one unit even in that case. (though that does encourage you to use hordes and legions when available)
since you can multi-charge a unit normally though my suggestion would be to give the defenders improved defense. either use the defense of the wall itself (7+) to reflect the protection, or give the garrisoning unit the benefit of “big shield” and “ensnare”. which in many cases might work out to similar results.