Sally port


The primary modern meaning for sally port is a secure, controlled entryway, as at a fortification or a prison. The entrance is usually protected in some way, such as with a fixed wall blocking the door which must be circumvented before entering, but which prevents direct enemy fire from a distance. It may include the use of two doors such as with an airlock. Many times they are driven through secured garages designed to pick up and drop off arrestees.

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