Note 354 — Chapter XI · MILITARY ARCHITECTURE IN THE LATER MIDDLE AGES: FORTIFIED TOWNS AND CASTLES

The barrel-vault of a basement chamber in one of the curtain-towers retains the marks of the wattled centering on which it was built. This is persistently asserted to be a mark of Roman origin. As a matter of fact, no part of the present castle can be proved to be earlier than the beginning of the twelfth century, when Roger of Poitou may have moved the head of his honour here from Penwortham, south of the Ribble. The castle, however, lies partly within, and partly outside the limits of a Roman military station.