Huntingdon Castle lies in the southern part of the town near the bridge, and can be accessed from either Castle Moat Road or Castle Hill. An early fortification may have existed on the site as early as the late 9th century, although all evidence of this has been destroyed by later developments. The castle was built in AD 1068 by William the Conqueror, consisting of a motte (castle mound) and semi-circular shaped bailey (enclosed courtyard) to the east. The castle was surrounded by a moat on three sides, the River Ouse providing protection from the south, and was destroyed in AD 1174 when it was besieged by Henry II’s armies. The defences were modified and the castle reused as a gun battery during the English Civil War, providing a highly strategic position controlling the main river crossing.
Despite being encroached upon by modern houses and the A14, the medieval motte and most of the inner bailey are visible today. Many of the ramparts dating to the Cromwellian period can also be seen.
When Edward the Elder, in 918, had defeated the Danes at Bedford (see TAMWORTH, LEICESTERSHIRE), he marched along the Ouse river to where, on a rising ground past Godmanchester, across the river, was the “Hunters’-down”, a post recently abandoned by the Danes, and of much importance, as it commanded the passage of the Ouse. Here he raised a strong fortress, the mound of which still marks its site, together with another mound on the opposite side against it. These wooden stockaded fortalices of the Saxons aided greatly the domination of England by the Normans, who, not only by their means were able quickly to perceive the strong and important military points for occupation in the country, but generally found in each post a lofty artificial mound, the earth of which had, after the lapse of ages, become sufficiently consolidated to receive the foundations and sustain the enormous weight of their massive keeps, which they could otherwise have reared only upon live rock, or an equally solid base.
Cotton asserts that Huntingdon Castle was erected by the Conqueror, who was here in 1068 ; and it is said to have been presented by Stephen to David, King of Scotland. Henry II., finding the place a retreat for rebels, ordered it to be razed to the ground. This, however, could scarcely have been carried out completely, as we find that De Bohun, the eldest son of the Earl of Hereford, and one of the guardians of Magna Charta, died in 1265, possessed of the castle of Huntingdon, or what remained of it. The generally received story is, that there were such frequent contentions for the possession of this castle between the Scots and the powerful family of St. Liz, that Henry, in one of his towering rages, swore that this cause of dispute should exist no longer, and decreed its demolition. Then, while degrading himself at the tomb of Becket, in 1174, he gave orders for the assembling of an army in the neighbourhood of London; and, when, in July of that year, he received word of the capture of William the Lion, he started at the head of his troops and advanced to Huntingdon, believing that the Scots, who held the castle, would at once surrender it, now that their King was in his power. And this they did, gaining permission to leave “scot-free” only, that is, safe in life and limb ; then he pulled down the castle.
Regarding this contest for its possession : When Waltheof was made Earl of Northumberland and Huntingdon by William I., he married Judith, the Conqueror’s niece, whose daughter, Maud, conveyed her inheritance in marriage first, to Simon de Liz, and, secondly, to King David I., son of Malcolm Ceanmore, King of Scotland, and the sainted Margaret, his wife, the niece of the Confessor. By this marriage the Saxon and Scottish dynasties were fused, and in this Scottish male line that earldom and the lordship of Huntingdon continued until Isabel, daughter and heiress of David I., Earl of Huntingdon, the brother of the Scots King, William the Lion, and Malcolm the Maiden, brought both in marriage to Robert le Brus; (see CONNINGTON), great-grandfather of King Robert the Bruce (see also FOTHERINGHAY, NORTHANTS). The castle stood in an excellent position for a fortress, bounded S. by the river, over which the site rises abruptly to a considerable height, and embracing from its summit a view over a very wide expanse of country. No vestiges of buildings exist, but there are traces of foundations remaining in the uneven surface. The outer ramparts enclose an area of several acres, being square in figure, with the angles rounded off. The chief entrance was on the E., and the whole was surrounded by deep ditches. The mound of Edward the Elder was surrounded also by a moat.
The shape and area afford strong evidence of a Roman origin, and it is most probable that here was the site of the station Durosiponte, rather than half a mile off at Godmanchester, which is low-lying, and an unlikely situation for a camp. Stukeley is of this opinion. (Castles Of England, Sir James D. Mackenzie, 1896)