Syon House

Has been described as a Possible Palace (Royal)

There are masonry ruins/remnants remains

NameSyon House
Alternative NamesSyon Abbey; Sion
Historic CountryLondon and Middlesex
Modern AuthorityLondon Borough of Hounslow
1974 AuthorityGreater London
Civil ParishBrentford and Isleworth

Bridgettine double house of Syon Abbey. The abbey moved here from Twickenham in 1431. It was dissolved in 1539, Richard Reynolds, one of the priests, being executed for refusing to take the Oath of Supremacy. He was canonized in 1970. The nuns returned for a short time when the house was refounded in 1557. Part of C15 undercroft survives in the present building. Retained by Henry VIII after the reformation as an occasional residence (Notably in 1542, when Catherine Howard, was housed in the cold, crumbling ruins of the convent, for several months, on her way to the Tower of London and execution) Protector Somerset reconstructed the house in 1547-52, substantially in its present shape.

Gatehouse Comments

The is a considerably bibliography of the historical and archaeological investigations of Abbey, but relatively little on the short period the site was used a as relatively low quality royal residence.

- Philip Davis

Not scheduled

This is a Grade 1 listed building protected by law

Historic England Scheduled Monument Number
Historic England Listed Building number(s)
Images Of England
Historic England (PastScape) Defra or Monument number(s)
County Historic Environment Record
OS Map Grid ReferenceTQ173766
HyperLink HyperLink HyperLink

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  • Goodall, John, 2011, The English Castle 1066-1650 (Yale University Press) p. 456
  • Thurley, Simon, 1993, The Royal Palaces of Tudor England (Yale University Press) p. 50, 57
  • Colvin, H.M., Ransome, D.R. and Summerson, John, 1982, The history of the King's Works, Vol. 4: 1485-1660 (part 2) (London) p. 272-3
  • Reynolds, Suan (ed), 1962, 'Heston and Isleworth: Syon House' VCH Middlesex Vol. 3 p. 97-100 online transcription
  • RCHME, 1937, An inventory of the historical monuments in Middlesex No. 86-88 no. 5 (plan) online transcription


  • Wessex Archaeology, 2003, Syon House, Syon Park Hounslow An Archaeological Evaluation of a Bridgettine Abbey and an Assessment of the Results (Wessex Archaeology 52568.05) online copy