(Berks) is Silicis castrum (flint camp), a Saxon-Latin form of the Roman Calleva or Galleva. Galleva is the Roman form of the British Gwal Vawr (great wall), so called from its wall, the ruins of which are still striking. Leland says, “On that wall grow some oaks of ten cart-load the piece.” According to tradition King Arthur was crowned here; and Ninnius asserts that the city was built by Constantius, father of Constantine the Great.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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