Ours are 22 feet wide and 375 long. wish they were longer some days but thats how it worked out using an existing barn. As far as the width, I like them at 22 feet or less so one person or kid can bring cattle up into the barn by them selves, even after the cattle get sick of it. Each of our runs goes into individual pens inside the barn. If I could start from scratch on open ground I would love pie shaped pens coming out of the barn. Butt if you are tight for space I would go with length over width, even if the runs have to be L shaped like ours.
Good luck!
Ron
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