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Photo: Caitlin from Hertfordshire, UK, CC BY 2.0 via Wikimedia Commons
Dates back to 900 AD, although only the gatehouse and some walls are remaining. The building is now the government office of Hertford Town Council, a museum, and an event space.
Hertford Castle is a Norman era castle built beside the River Lea in Hertford, the county town of Hertfordshire, England. Most of the internal buildings of the structure have been demolished.
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