Image copyright Jon Boston Image caption Restorers were 'stunned' to discover what lay beneath the surface of the pond

Historians have been left baffled after the discovery of a rare Victorian 'pool' hidden beneath a fish pond.

Restoration work in the gardens of 150-year-old Ham Manor in Llantwit Major, Vale of Glamorgan, revealed the long-forgotten secret.

Thought to be a wallowing pool, it was only discovered when water was drained from the historic ornamental pond.

However, some local historians admit they are 'puzzled' as to what the sunken structure was used for.

The pond had remained largely undisturbed since the manor house, designed by the prominent architect Sir Matthew Digby Wyatt, was built in 1869.

But when restoration began, workers were "amazed" to discover what lay in the centre.

Local archivist and chairman of Llantwit Major History Society said it was a "peculiar" find.

He said: "It is a fascinating discovery that is puzzling a lot of local historians, including those who have studied the house.

"We have no knowledge of any other large house in the area having anything similar to this."

The current owners said they have been told by historians it is a "perfect example" of a Victorian wallowing pool built of locally quarried Welsh bluestone.

Image copyright Jon Boston Image caption For more than 100 years, the park's pond has been home to fish and water lilies while its secret lay hidden

Fed by natural rainfall, residents would relax either knee deep on the top benches or chest deep on the lower tiers.

David Curson, operations manager for Berkeleyparks, which owns Ham Manor, said they have been inundated with requests to see the pool.

He said: "It was a stunning find and something which nobody suspected existed.

"Very few examples of these structures still exist and when news about it got out, we started receiving requests for visits from historians and archaeologists from across the country.

"[However] the decision was taken to return the pond to its function of the past hundred years and now our koi carp have their home back.

"It's certainly added another layer of charm and mystery to this lovely garden."