It was situated on the north bank of the main branch of the river, thirty miles from the sea.

It extended about nine hundred yards along the bank, and was six or seven hundred yards wide, at its broadest part.

Beyond the town were some suburbs, outside the palisade that inclosed it.

The palisades were ten or twelve feet high, strengthened by embankments of earth thrown up against them, on the inner side.

One face of the defences ran along the river bank, while the others were protected by a shallow creek communicating with the river.