When Sutton Knoll (Rockhall Wood Geological SSSI) recently attracted the attention of GeoSuffolk members, although it had been a site for study for more than 170 years, it was a largely overgrown, albeit important, mound in the beautiful Suffolk countryside overlooking the River Deben. Five years on, after much hard work and planning, site clearance, and exposures carefully logged, an information panel has been ceremoniously unveiled giving details of a Pliocene Island site both famous and unique and still holding much potential for research.

There were twenty in attendance on May 14th, including Dr and Mrs Richard Hamblin representing East Midlands Geological Society which had given a donation towards the panel following a field trip in 2007; Dr Jonathan Larwood from Natural England; Neil Lister from Suffolk Coast and Heaths AONB; Professor Richard West of Cambridge, whose research on fossil pollen identified the types of trees growing during the time the Coralline Crag was deposited; Elizabeth Hall of The Lion Associates who produced the panel; and Guy and Jenny Quilter who own Sutton Knoll as part of Sutton Hall Farms and without whom the whole venture would not be possible.

Bob Markham, Chairman of GeoSuffolk spoke first, recounting earlier visitors to Sutton Knoll with original copies of two fascinating publications - The Crag Mollusca by Searles Valentine Wood 1848 and Joseph Prestwich’s paper on his survey of Sutton Knoll from the Quarterly Journal of the Geological Soc. London 1871.

Barry Hall, who has undertaken management of Sutton Knoll and development of the interpretive panel, introduced Jenny Quilter who snipped the red ribbon round the panel and declared it officially open. Barry then gave a brief overview of site management and explained the detail on the panel - a diagram of the island during Red Crag times (by Dr Roger Dixon), a map of the site and illustrations of fossil specimens.

Roger Dixon spoke of his research at Sutton Knoll and explained the unique importance of the site: the London Clay, the Coralline Crag which has yielded over 300 species of mollusc and many bryozoan fossils and the Red Crag which surrounds the Coralline Crag ‘island’, yielding a beautifully preserved autochthonous mollusc fauna where it forms the ancient beach. He concluded by producing a newly commissioned painting reconstructing the Red Crag beach and sea lapping against the Coralline Crag island.

Bob Markham presented Jenny Quilter with a framed copy of Joseph Prestwich’s map of Sutton Knoll and champagne and sandwiches conjured up in the middle of the Suffolk fields (courtesy of Roger Dixon and Caroline Markham) concluded the unveiling.

There followed a tour of the Knoll beginning with the ‘Pliocene Forest’, the most recent addition to the interpretation of the site. Bought with a grant from the Geologists’ Association Curry Fund, four trees representative of genera identified by Professor West from pollen in Pliocene deposits at nearby Orfordness have been planted. These are: the conifer, Sciadopitys verticillata (Sciadopitysaceae), also known as the Japanese umbrella pine; Tsuga heterophylla and Tsuga canadensis (Pinaceae) and Liquidamber styraciflua (Hammamelidaceae) or Sweet Gum.

Sutton Knoll SSSI is owned by Sutton Hall Farms. The interpretive panel and north face of Sutton Knoll can be viewed from the public footpath northeast of Rockhall Wood at TM 305441.