Sarum, now known as Old Sarum, was first occupied by Neolithic peoples, some 5,000 years ago. The site of their village was a slight hillock in the middle of an otherwise featureless plain. Earthworks were originally used to fortify and secure the settlement, and there is evidence that they farmed the surrounding area, primarily in the flatlands along the River Avon.

Life continued in this simple manner until around 600 BC. A second phase of construction increased the height of the outer wall and deepened the surrounding ditch. It is likely that the earthworks were topped by a wooden palisade. There is no evidence of a rock wall at this location. The enclosed area was approximately 55 acres, being a rough oval of 1,650 feet by 1,880 feet.

With the coming of the Romans in 53 AD, life within Sarum was little changed. The Romans set up their garrison outside the walls of the structure, in the area which is now known as Stratford sub-Castle. However, there was considerable trading with the native population, as evidenced by finds of Roman coins of the period within the enclosure. The place must have had some importance, as there are four Roman-built roads which converge on the place.

The withdrawal of the Romans opened the door for the Saxons, who were quick to take advantage of the situation throughout Romanized Britain. The Saxon's were, in turn, displaced by the Norman invaders. In the latter part of the eleventh century, the newcomers built a motte in the center of the existing fortification. The motte stands some twenty feet above the surroundings and near thirty feet above the surrounding ditch. On the top of this artificial mountain, they constructed a wooden keep, which was replaced in 1100 by a massive stone structure. In 1130 AD, a royal palace was erected within the banks, and a town wall was built outside the original earthworks. Meanwhile, the clergy were also actively building. The first cathedral was completed in 1095, but burned down just 5 days after it was consecrated. A new edifice was built on the spot, and completed around 1190, bigger and better than the first. However, relations between the palace guard and the clerics were apparently not good. Frequent outbreaks of violence led Bishop Richard Poore to relocate his cathedral to the other side of the River Avon. A thriving settlement grew up around the new cathedral and, by the middle of the thirteenth century, "Old" Sarum was in decline. New Sarum continued to grow and today is known as the town of Salisbury.