The height of the wall was 8 feet, and at intervals of 30 yards apart towers were raised 10 feet above it, one of these being placed at either side of the entrance.

Here the bank was cut away, and solid buttresses of masonry supported the high gates.

The opening in the outer bank was not opposite to the gate in the inner, being fifty yards away, so that any who entered by it would have for that distance to follow the ditch between the two banks, exposed to the missiles of those on the wall before arriving at the inner gate.
Five hundred men laboured incessantly at the work.

The stone for the walls was fortunately found close at hand, but, notwithstanding this, the work took nearly six months to execute; deep wells were sunk in the centre of the fort, and by this means an ample supply of water was secured, however large might be the number within it.
A very short time after the commencement of the work the news arrived that King Edmund of East Anglia had gathered his forces together and had met the Danes in a great battle near Thetford on Sunday the 20th of November, and had been totally defeated by them, Edmund himself having been taken prisoner.

The captive king, after having been for a long time cruelly tortured by the Danes, was shot to death with arrows.