Samuel Pepys' visit to Old Sarum and Salisbury in 1668
Samuel Pepys , travelling from Hungerford, passed Old Sarum in the dark on his way to Salisbury on 10th June 1668.
His diary  entry was:
"So all over the plain by the sight of the steeple (the plain high and low) to Salisbury by night; but before I came to the town, I saw a great fortification, and there light, and to it and in it; and find it prodigious, so as to fright me to be in it all alone at that time of night, it being dark. I understand since it to be that that is called Old Sarum.
Come to the George Inne, where lay in a silk bed; and very good diet. To supper; then to bed."
It looks like there was a light to and in Old Sarum but he means they alighted from their coach to visit it. It must have been late as it was a June day.
Prodigious then meant more than just large or multiple, it implied spooky or unnatural, a nuance lost today. He is referring to the earthworks.
The George Inne was a coaching inn on the High Street dating from 1364. Pepys thought it exorbitant. Its name derived from the Guild of St George, formed in 1306 by the Mayor and Corporation and is retained today as the Old George Mall. Its entrance is now the entrance to the mall . The Royal George Inn on Bedwin St did not yet exist. He was accompanied by his wife Elisabeth, their maid and his mistress Deborah Willett, Betty Turner and Will Hewer . The following night on the way to Bath to visit Deborah’s uncle, Deborah and Betty shared a truckle bed with each other and the room with the Pepys in a little inn somewhere before Beckington. Both beds were lousy .
 Halys, John. 1666 Portrait of Pepys https://en.wikipedia.org/wiki/Samuel_Pepys
 Pepys, Samuel. His diary entry of 10th and 11th June 1668
 Boyle, Brian, 2011 as a secondary source https://www.closedpubs.co.uk/wiltshire/salisbury_george.html
 Tomalin, Claire. 2002 Samuel Pepys The Unequalled Self.
There were two ladies named Betty Turner in the diaries, one the daughter of Jane (née Pepys), a cousin, one the daughter of Elizabeth, a Navy Office neighbour. (note 20 p 426) This was more likely the former. Will Hewer was Pepys’ servant and clerk, ten years younger than he, nephew of a colleague Robert Blackborne, secretary to the naval commissioners and customs and son of a stationer (p121)
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