Old Bailey, The: The principal criminal court of England, situated on the street named Old Bailey, which runs from Newgate to Ludgate Hill, not far from St. Paul's, London. It was the site of the Roman vallum, forming part of the city's fortifications external to the Wall, hence Ballium and Bailey. A vallum was a rampart of palisades, so called from vallus, a stake, and was planted on the top of the agger, or mound, thrown up for the purposes of defense.

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