Odd sort of place, Old Sarum; an Iron Age hill fort, with a Norman castle in the middle, together with the foundations of an old cathedral, and some evidence of a medieval town.
The hill fort was continuously occupied right through to the end of the Roman period in the the fourth century. What happened after that is unclear, but it seems likely that there were Anglo-Saxon occupants and that it was a place of some importance.
Soon after the Normans invaded in 1066 they built the castle, the earliest records of which date back to 1069-70. The earliest stone building, the keep, dates from around 1130.
Next to the castle, the small cathedral which was begun around 1075, and was greatly extended in 1130 under Bishop Roger who also built an adjoining Bishop's Palace.
However space was very restricted, and relations with the occupants of the castle became strained. Finally in 1220 the clergy had had enough, and they decided to up sticks and move to a new site at New Sarum, the current Salisbury Cathedral. The old cathedral was demolished and the best of the stone reused in the new building. The castle remained in use, albeit in an increasingly poor state of repair, until 1514 when Henry VIII sold it to one Thomas Compton.
We know little about the town that used to surround the castle and spread down the hill outside the gates, but by 1540 when John Leyland visited there was nobody living there.
We do know from a Poll Tax return that in 1377 there were 3,226 tax payers living in Salisbury, and only 10 in Old Sarum, so it would seem that almost everyone decamped down the hill soon after the cathedral moved.
Despite the fact that there was nobody living there, the 'town' continued to send to two member to Parliament right up until the Great Reform Act of 1832 that finally abolished the so called 'rotten boroughs'.
What you see today is largely the result of aggressive excavations carried out between 1909 and 1915 under Lieutenant-Colonel William Hawley of the Society of Antiquarians in London.
As was common in those days, the work was poorly recorded, and much evidence was destroyed.
Apart from the Treasury, the cathedral exists in outline only (and some of that is controversial). More substantial remain exist of the castle, although it is hard to imagine it as a working building; the views however are terrific, and worth the entrance fee alone.
The circuit of the Iron Age walls is about a mile in length, and shouldn't be missed as they are probably the most impressive structure on the site.
The hill fort and cathedral are open to the public at all times. For opening times, admission prices, etc. for the castle, please see English Heritage's official site detailed below.
Although I must have driven along the A345 past Old Sarum hundreds of times, I never noticed the inscribed stone marking one end of Mudge's Line.
Had I spotted it, I would probably have dismissed it as yet another standing stone.
According to the display board up on the ramparts of Old Sarum, in 1794 in order to check the accuracy of the first mapping of Southern England, Lieutenant William Mudge laid out a 36,574 foot (11,253 metre) long base line from which to plot the positions of distant places using a huge theodolite made in 1791 by Jesse Ramsden.
The stone dates from 1967. For some reason the masons chose a typeface that makes the inscription almost impossible to make out. As far as I can see, it reads:
In 1794 a line from this site to Beacon Hill was measured by Capt W Mudge of the Ordnance Survey as a base for the triangulation of Great Britain