Diaulos (architecture)

Diaulos, (from Gr. δι-, double, and αὐλός, pipe) in ancient Greek architecture, was a peristyle round the great court of the palaestra, described by Vitruvius, which measured two stadia (1,200 feet (370 m).) in length, on the south side this peristyle had two rows of columns, so that in stormy weather the rain might not be driven into the inner part.

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