Probably not quite the ‘pen’ thought of for this challenge,
My old wool shed.
Under the left skillion Is where sheep stand waiting to be shorn.
These are called ‘sweating pens’
The shearer’s operated at the far end of the gable roof line.
Under the gable were catching pens.
Here shearer’s would have a pen of sheep each.
They would catch a sheep drag it onto the ‘board’/floor
and shear it prior to realising it into their letting go pen,
where the sheep would remain for each two hour work period
after which, all sheep would be counted and
each shearer would have those sheep added to his totals.
At the top of this image I have noted the sheep yards.
A collective term.
Sheep yards are comprised of many smaller yards/pens.
At livestock selling centres, it is not unusual to see 50,000 sheep
sold through the yards, on sale day, during peak periods.
However, there will also be hundreds of numbered selling pens
so each owner can identify their sheep.
The text ‘sheep yards cans also be called pens’ is my largest pen.
There are, including counting out pens,
nine other pens of diminishing sizes along with two races
used for drafting and animal husbandry purposes.
And that is my pen post.