This pen is 12 X 15 with 6' sides.  I have 3 pens like this which I can move in and out.  I put her in this one because I didn't have the rest of the barn bedded yet and with her so close to calving, I didn't want to bother her.  The whole barn is about 50 X 80 with 1/2 of it covered.  It was an old airport hanger that my dad moved here 50 years ago.