This is of Henry III's time though it has been much cut about and modernised. It had originally a single room on each floor and remains of embrasures and the large stone fireplace can be seen.
There are a number of prisoners' inscriptions, mostly of early 17th century, about the time of the Gunpowder Plot. This tower was formerly inhabited by the Keeper of the Crown Jewels and was the scene of the attempt by Colonel Blood in 1673 to steal the Crown and other regalia.