Burgh Castle is a village and civil parish in the English county of Norfolk. It is situated on the east bank of the River Waveney, some 3.7 miles west of Great Yarmouth and within the Broads National Park. The parish was part of Suffolk until 1974.
Burgh Castle is the site of one of several Roman forts constructed to hold cavalry as a defence against Saxon raids up the rivers of the east and south coasts of southern Britain . Possibly this was Gariannonum, a name that appears in a some sources; the identification was once thought secure, but is now thought doubtful by specialists. The fort is roughly rectangular, approximately 205 m by 100 m , with three of the tall massively built walls still extant; the fourth fell into what was once an estuary but is now a marsh, Breydon Water.

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