If you can, walk round Portchester Castle to the Watergate and enter it the way that most Romans would have first seen it.
Standing there, looking across the wide expanse of water to Portsmouth and the Isle of Wight beyond, it seems a strange place to build a castle.
Not much use to defend the harbour from attack from the sea,
but perhaps that is the point.
There is a clue in the name; it is first and foremost a Port and then a Chester (castra - castle).
The original Roman fort is believed to have been built between CE 285 and 290, at a time when barbarian pirates were launching attacks along the coasts of Britain and Gaul. Tucked away out of sight from the sea, and about as far inland as it was possible to get by sea-going boat, Portchester would be the ideal place for a transit camp and warehouse.
The site appears to have been continually occupied after the Romans left, but not much changed until the Normans came along.
Desperate to secure anywhere defensible, they built a castle in one corner of the old square enclosure, together with a church (and briefly a priory) in the opposite corner. It is a measure of how large the Roman Fort was that a medium sized castle fills less that a quarter of the site.
Little is known of the early history of the castle; the Keep and Inner Bailey wall we see today probably date from around 1140 when it was held by the splendidly named William Pont de L'Arche.
Various domestic buildings were added to the Inner Bailey over the years: the South and West Ranges were built by Richard II between 1396 and 1399, and the East Range by Sir Thomas Cornwallis, Constable of the castle under Elizabeth I, in the early seventeenth century.
The castle led a largely uneventful life. From time to time it was pressed into service as a prisoner of war camp, but it never saw any military action.
Easily missed are the wall paintings on the second floor of the keep, so easily missed that I had to go back in to find them. These date from some time after 1830 when this part of the castle was used as a theatre.
There is an audio guide, which may be very good. I gave up after being introduced to a soldier and a prisoner-of-war with a 'zilly French accent'. I'm all for audio guides such as the one at Portland Castle were a knowledgeable and informed guide points out features of interest. I have to be in the right mood to listen to unknown actors performing the scripted recollections of imaginary characters. It doesn't happen very often.
For opening times, admission prices, etc. please see English Heritage's official site detailed below.
St Mary's Church
In around 1130 Henry I founded an Augustinian priory within the walls of the castle. It didn't last long though, as the monks upped sticks and moved to Southwick between 1147 and 1150.
The current St Mary's Church is the one built by William Pont de L'Arche for this community, although there was an earlier church on this site.
The church is virtually unaltered, apart from the East Window inserted in around 1601 by Sir Thomas Cornwallis who also demolished the derelict South Transept.
There are many fine Norman architectural details, especially the splendid West Door.
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