1 Earith to Needingworth via Bluntisham – due 2020
2 Needingworth to St Ives via Holywell – due 2020/2021
3 Additional walk into Ouse Fen, RSPB nature reserve
4 & 5 Additional walks from St Ives to Godmanchester (and Huntingdon) and back to St Ives
For a key to the geology see the British Geological Survey map viewer.
This part of the Trail explores the valley of the River Great Ouse, one of the major rivers that drain into the Fenland Basin. As well as being an important area for wildlife, the valley is an ancient route, travelled by water and by land, and contains significant historic sites as well as the picturesque towns of St Ives and Godmanchester. Having arrived in Earith from Somersham, to the north, the Trail heads west, upstream, with a walk that starts at a viewpoint overlooking the place where the river divides in two as it empties into the Fens. The two major channels that take the waters across the Fens to the Wash are the Old Bedford River, that takes the majority of the water in a direct, and heavily embanked course, through the Ouse Washes and north west of the Isle of Ely to Denver in Norfolk, and the Old West River which winds its way to the east of the Isle and merges with the River Cam before heading north to rejoin the main channel at the Denver Sluice.
The first walk heads upriver to Needingworth, via Bluntisham, and the second walk continues on, via Holywell to the historic town of St Ives. Although the main Trail then heads south to Fenstanton, an optional extension takes you further upstream through one of themost attractive sections of the river, via Houghton to Godmanchester and the extensive, and very biodiverse, Portholme Meadow. A short further walk takes you into the town of Huntingdon. The return walk takes you back along the south side of the river via the Wildlife Trust’s Godmanchester Nature Reserve and the Hemingfords. The RSPB is developing a large area of disused gravel pits for wildlife conservation, Ouse Fen, which can be visited as a detour from the first walk.
The geology of the valley has been important economically due to the large amounts of sands and gravel that were deposited in a series of River Terraces at various times in the last half a million or so years when glacial meltwater formed much larger and stronger rivers through the valley. Some of the excavated areas are now mostly flooded and are being developed as wetland areas for wildlife conservation. For more information on the formation and geology of the valley see the website of the Cambridgeshire Geological Society.
© Cambridgeshire Geological Society