Castlefacts³

Portbury Mound

Has been described as a Questionable Timber Castle (Motte)

There are cropmark/slight earthwork remains

Name	Portbury Mound
Alternative Names
Historic Country	Somerset
Modern Authority	North Somerset
1974 Authority	Avon
Civil Parish	Portbury

Prior writes "Between 1134 and 1154, Fitzharding erected a motte at Portbury in order to exploit the possibility of trade with Bristol, its port, and the River Avon." he gives the above map reference which is a hill top on the edge of the parish. Prior gives no other citation. In his PhD thesis he gives the following additional description 'Low Motte (8.00m in dia. x 0.80m high) with a flat top, situated atop a plateau, with naturally steep slopes on E, S, and W sides. Possible bailey and outworks (60.00m of a bank orientated ESE-WNW, centred at ST 5097 7470, 5.00m wide x 7.00m high). Poorly defined earthworks'.

"A second camp is half a mile to the east-south-east' of Portbury Camp, Conygar Hill (Dobson).

The area concerned is a plateau-like hilltop with fairly steep natural slopes on all sides except the north. The only earthwork of any significance comprises 60.0m of a bank orientated ESE-WNW, centred at ST 5097 7470. It is 5.0m wide overall, and up to 0.7m high, with a strong content of stones. There is no outer ditch. No southerly turn can be traced, but if it formerly did so it would result in a rectangular enclosure bounded on the S. and W. by natural slopes.

Except for its breadth the bank could be the remains of an old field boundary.

At the highest point on the plateau at ST 5094 7467, there is an artificial mound of earth, 8.0m in diameter and 0.8m. high, with a flat top. From its position it could be a barrow or a windmill mound, but it is ditchless, and there is no trace of a cross-tree depression.

At ST 5095 7467 there is a circular pit 7.5m. in diameter, 0.5m deep on the E. and 0.3m deep on the W. It is grass covered, and would seem unlikely to be a pond or a quarry pit.

The origin and purpose of all these earthworks is obscure. The bank may be that accepted on the OS 1" 1830 as part of a camp, and it may be that this publication has given rise to the further acceptance in Dobson (F1 NVQ 12-FEB-62)

(PastScape)

Gatehouse Comments

Nothing shows on air photo and nothing on the map suggests this as a medieval centre (no paths or roads lead to the site which is isolated from medieval settlement and lies on a parish boundary). This seems a fanciful identification of some uncertain earthworks in a position quite untypical for a castle without any other supporting evidence. Even if there were some supporting evidence for a castle at Portbury then the obvious site for such a castle would be the small Iron Age camp on Conygar Hill (at ST49897509 - NMRN 195214), which does have a mound within it although this is identified as a possible pillow mound (medieval rabbit warren). Portbury was the centre of one of the Hundreds of Somerset. Collinson states FitzHarding had a residence at Portbury but does not locate it. He also states he procured a market and fair for Portbury which would be a more certain way to exploit trade than to build a castle.

- Philip Davis

Not scheduled

Not Listed

Historic England (PastScape) Defra or Monument number(s)

198601

County Historic Environment Record

map.n-somerset.gov.uk/her.html

OS Map Grid Reference	ST509746
Latitude	51.4688606262207
Longitude	-2.70766997337341
Eastings	350940
Northings	174670