The Fens have been inundated by the sea on various occasions as shown by the marine silts and clays that can be found over large areas, even in the southern fenland of Cambridgeshire. The complex history of freshwater marshes changing to salt marshes and back again, for example in the Late Neolithic/Early Bronze Age and in Romano-British times, has left interwoven peat and silt/clay layers that reveal the timing and extent of the ‘flooding’ in each local area. See the Fen Edge Trail website for more information.

A lidar image of the island of Thorney shows the remnants of tidal creeks (roddons) in the surrounding fields (often visible by the change in height and colour of the soil).

New Local Geological Site

The Great Fen: Holme Fen and Whittlesea Mere LGS

We are very pleased to announce that our latest proposal for designation as a Local Geological Site (LGS) was recently (Feb 2020) approved by the County Wildlife and Geological Sites Panel. The site is the Great Fen: Holme Fen and Whittlesea Mere LGS and comprises the land in the northern part of the Great Fen that is owned by The Wildlife Trust BCN and Natural England. We are grateful for the help of Dr Steve Boreham (University of Cambridge) who will be representing CGS on the Great Fen Joint Technical Advisory Committee.

The site has qualified as an LGS under all four categories – Scientific, Historical, Educational and Aesthetic.

For more information see The Great Fen LGS page

A superb mammoth tusk is now part of the Sedgwick Museum’s new Ice Age display.

Sir John Franklin’s ill-fated expedition to the North-West Passage has often been in the news ever since he left England on the 19th May, 1845 never to return. Successive searches throughout the 19th century eventually found artefacts and human remains. But it was not until 2014 the wreck of Franklin’s ship, HMS Erebus was found and two years later the wreck of HMS Terror. Now the extraordinary story of HMS Erebus is receiving new publicity thanks to the publication of Michael Palin’s new book – ‘Erebus : the story of a ship’. Whilst the earliest searches did not find any traces of Franklin and his crew, one of them, led by Captain Kellett did find this amazing mammoth tusk. More here

Photo of tusk copyright Sedgwick Museum

The Sedgwick Museum’s Ice Age exhibit, tells the story of the latter part of the ‘Ice Age’ as experienced in the east of England. The exhibit uses the amazing animal and plants remains recovered from historic sites near Cambridge, at Barrington, Barnwell and Burwell to show the extraordinary variety of animals that lived in the area. They ranged from warm climate hippos, rhinos, elephant, lion and hyena to cold adapted woolly mammoth and woolly rhino. They illustrate the dramatic impact that climate change had on life and environments during a typical interglacial-glacial-interglacial cycle.

Recent finds have been made during the new A14 construction including woolly mammoth and woolly rhino at Fenstanton. More here

The fenland has always been a land of mystery. This is particularly true when trying to unravel the complex history of dynamic changes in the landscape, which are directly linked to both sea level and climate. Thanks to an increase in research in recent years, much has now been discovered that is finally providing a picture of life in the fens since the end of the last ice age.

Although a few important sites are protected in law (as SSSIs), CGS is now looking at others that can be developed to help people explore and understand the geology of the fenland and its associated cultural history. Nature reserves such as those of The Great Fen, the Ouse Washes and at Wicken Fen, have information available about the local landscape but we are now investigating the possibility of designating an area as a Local Geological Site. This would highlight the importance of the geology locally, regionally and nationally.

The area being considered is that of the northern part of the Great Fen, which includes peat fen, remnants of raised bog, lake marl, silt fen and roddons. The land here also has links with local history and culture (Whittlesey Mere, ancient waterways such as the old River Nene, and limestone ‘blocks’ being transported from quarries at Barnack). It is also of high landscape value, containing the site of the Holme Fen Post and having geological links to the nearby ridge at Yaxley. The potential educational value, through the Great Fen, and its partners, is considerable. More news on this soon.

Built around 1860, these listed buildings are the remains of a thriving clunch quarrying industry in this Fen Edge village. Three of the kilns are preserved, with the fire hearths visible inside. The clunch rubble was loaded in through the circular openings at the top after being carted up the ramp. Fires were fuelled with coal and burned continuously. Quicklime was raked out at the bottom as the final product. Work stopped around 1935. These are now listed buildings. The site of the kilns is now a Local Geological Site.

The interiors may still house bats, so please approach and view the kilns (from the outside) with consideration.

See our Fen Edge page for more information on the local geology and its economic use, produced as part of our Geosites work on the seven Landscapes in the county of Cambridgeshire.

Isleham is the finishing point of our Fen Edge Trail which links the village to others on the edge of the Cambridgeshire Fens, from Peterborough, via Ramsey, St Ives and Cambridge to here on the border with Suffolk.

Location (Open Street Map)

View of kiln entrances

Circular loading opening with access ramp