A 500-year-old Norfolk manor house has had its entry on the nation's heritage list upgraded because of its unusual interior.

Northwold Manor, which stands on the High Street of the medieval village, between Downham Market and Thetford, was granted Grade II listed status in 1951.

But what lies behind the imposing front door of the house, which is not open to the public, was not included.

Thetford & Brandon Times: Northwold Manor has had its listing upgraded to Grade II star because of its unique interior Northwold Manor has had its listing upgraded to Grade II star because of its unique interior (Image: Historic England)

Now the manor house, with its inter-connecting rooms and unusual lack of corridors, has been reappraised as having exceptional architectural and historic interest because it reflects 500 years of a variety of architectural styles from the 16th through to the 21st century.

Historic England, which has changed its listing to Grade II star, describes it as "a time capsule of the evolution of architectural design which is rarely seen in a single building".

It is one of 44 historic places added to the east's National Heritage List in 2023. 

Thetford & Brandon Times: The interior of Northwold Manor has been described as 'a time capsule' by Historic EnglandThe interior of Northwold Manor has been described as 'a time capsule' by Historic England (Image: Historic England)

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Heritage minister Lord Parkinson said: "The great work done by Historic England will ensure that they are protected for future generations to enjoy and to learn about the fascinating people and stories connected with them." 

Thetford & Brandon Times: The interior of Northwold Manor has been described as 'a time capsule' by Historic EnglandThe interior of Northwold Manor has been described as 'a time capsule' by Historic England (Image: Historic England)

Duncan Wilson, chief executive of Historic England said: “We’ve examined and protected some amazing sites this year, which together give us a window into our rich and varied historic environment."

He said people were being encouraged to add their own memories and pictures to Historic England's Missing Pieces Project for others to see and enjoy.Thetford & Brandon Times: The interior of Northwold Manor has been described as 'a time capsule' by Historic EnglandThe interior of Northwold Manor has been described as 'a time capsule' by Historic England (Image: Historic England)

Sitting on a one-acre plot within a walled garden, Northwold Manor has been adapted over time by continual expansion and is now around 60m long and resembles a village high street property more than a family home.

Once owned by the Carter family - relatives of British archaeologist and Egyptologist Howard Carter - highlights include a ballroom from the Regency period, a 16th century range, impressive 17th century oak staircase, panelled 18th century parlours and a classical archway into the first-floor porch chamber with fluted ionic columns.