Marlborough Mound: a sibling for Silbury Hill?

Marlborough Mound Profile © English Heritage

Marlborough Mound Profile © English Heritage

The Wiltshire landscape around Avebury and Silbury Hill is the heart of prehistoric Britain, and has World Heritage designation. Now another monument can be added to its archaeological treasures: the Marlborough Mound.

Marlborough Mound © Marlborough College

Marlborough Mound © Marlborough College

The Mound, in the grounds of Marlborough College, was already recognised as a feature of considerable historical significance. It was the motte on which the keep of Marlborough Castle was built fifty years after the Norman Conquest and it subsequently became the centrepiece of a major seventeenth century garden. The latest research has extended its history back by three millennia.

Recent coring of the mound at Marlborough College produced four samples of charcoal, allowing radiocarbon dating for the first time. The samples, which came from different levels in the mound, were taken from two bore holes through the height of the 19m monument, showing that it was built in the years around 2400 BC. This is the first firm evidence proving the theory that the castle motte is largely a re-used prehistoric structure of the highest national standing.

For centuries people have wondered whether it is Silbury’s little sister; and now we have an answer

Jim Leary, who led the recent archaeological investigations for English Heritage at the nearby Silbury Hill, and is co-author of the recently published ‘The Story of Silbury Hill’ coordinated EH’s contribution, which also included radiocarbon dating. He says, “This is an astonishing discovery. The Marlborough Mound has been one of the biggest mysteries in the Wessex landscape. For centuries people have wondered whether it is Silbury’s little sister; and now we have an answer. This is a very exciting time for British prehistory

Aerial view of Silbury Hill. Image: cryptoworld, Flickr

Aerial view of Silbury Hill. Image: cryptoworld, Flickr

After the prehistoric mound was re-used as a castle motte – the only known example of its kind – it became an important royal castle for the Norman and Plantagenet kings. It was occasionally the scene of major political events, such as the general oath of allegiance to King John in 1209, as well as being a favourite royal hunting lodge. In the fourteenth century the castle passed to the queens of England, and gradually became neglected.

In the seventeenth century it came into the possession of the Seymour family, and its next avatar was as a feature in a historically significant early romantic garden: a spiral ramp was cut in its side, with a hawthorn hedge enclosing the path which wound to the summit, where there was a water feature.

The Master of Marlborough College, Mr Nicholas Sampson, said: ‘We are thrilled at this discovery, which confirms the long and dramatic history of this beautiful site and offers opportunity for tremendous educational enrichment.’

The work is part of a major conservation programme being undertaken by the Marlborough Mound Trust, specially formed at the invitation of the College and under the coordination of Donald Insall Associates. The Chairman of the Trust, Mr Michael Macfadyen says, ‘The inspiration for this was our founder Eric Elstob, a former pupil at the College, whose generous legacy has provided the means for this work. He would have been totally delighted by this news.’

Please note: As part of the College grounds, the Mound is on strictly private property.

English Heritage information on Silbury Hill: http://www.english-heritage.org.uk/caring/conservation-projects/silbury-hill/