Hertfordshire, by a route, upon which the ravages of the Normans are
clearly indicated in _Domesday Book_,[5] to a position on the north of
London, thus gradually severing its communications with the rest of
England, so that neither men nor convoys of provisions could enter its
walls. Placing camps at Slough, Edmonton, and Tottenham, William himself
remained some distance to the rear of these last with the main body of
the army, and it seems probable that the actual surrender of London took
place at or near Little Berkhampstead, in Hertfordshire,[6] some four
miles to the east of Hatfield, and then about eighteen miles to the
north of the city, which could be seen in the distance from the high
ground hard by.

According to Orderic, William, after his coronation at Westminster,
spent some days at Berkhampstead, during which "some fortifications were
completed in the city for a defence against any outbreaks by its fierce
and numerous population."[7] Meagre in details as is the history of this
early period, it would appear from the foregoing passage that William
caused two castles to be erected, one at either end of the city, hard by
the river bank, the western one becoming the castle of that Ralph
Baynard who gave his name to it and to the ward; the eastern one (after
the building of its stone keep) receiving the appellation of the Tower
of London.

When erected on new sites, the early castles seem to have consisted of a
bailey, or court, enclosed by wooden palisades, and a lofty circular
mound, having its apex crowned by a wooden tower dwelling, also within a
stockade, the whole enclosed by a ditch common to both; but though
nothing remains of these early castles in London, it seems probable that
the mound was dispensed with, and that the angle of the wall was
utilized to form a bailey, the side open to the city being closed by a
ditch and bank, crowned by stout palisades of timber, while the Roman
wall would be broken through where the ditch abutted upon it at either
end, the whole bearing a strong resemblance (allowing for the difference
in the site) to the castle of Exeter. Orderic goes on to say that
William at once built a strong castle at Winchester, to the possession
of which he evidently attached greater importance than that of London,
where the great stone keep was probably not even commenced till quite a
decade later, though Pommeraye, in a note to his edition of _Orderic_,
tells us "that it was built upon t