You are looking at a command called face

face {object} to|to the|towards|leading|facing|heading {direction}

When you face a doorway object its linked doorway (exit) object gets the opposite direction.

face the farm to the north
face the ladder leading down
face the castle west
face the cliff facing east


You can go in the direction you face it just by typing the direction eg up, north, west etc..

Check the exit at the other end of the faced object and it will face back in the opposite direction. (you see a ladder leading up)
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