Walking in the North Wessex Downs. Steve Davison
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Walk 13 Ramsbury and Littlecote
Walk 14 Mildenhall and the River Kennet
Walk 15 Marlborough and Savernake Forest
Walk 16 Ogbourne St Andrew, Rockley and Barbury Castle
Walk 17 Fyfield Down and the Devil’s Den
Walk 18 Avebury
Walk 19 Cherhill and Oldbury Castle
Walk 20 Heddington, Oliver’s Castle, Roundway Down and Morgan’s Hill
Walk 21 Alton Barnes and the Wansdyke
Walk 22 Knap Hill and Oare
Walk 23 Martinsell Hill and Wootton Rivers
Walk 24 Great Bedwyn and Wilton
Walk 25 Tidcombe and Hippenscombe Bottom
Walk 26 Inkpen and Walbury Hill
Walk 27 Ashmansworth and Faccombe
Walk 28 St Mary Bourne and the Bourne Valley
Walk 29 Ecchinswell and Ladle Hill
Walk 30 Kingsclere and Hannington
Appendix A Route summary table
Appendix B Useful contacts
Appendix C Further reading
The Devil’s Den – three large sarsen stones seen on Walk 17
INTRODUCTION
Looking north across The Manger and the Vale of White Horse from the Uffington White Horse (Walk 11)
The North Wessex Downs Area of Outstanding Natural Beauty (AONB), the third largest AONB in England, covers an area of 1730 sq km and takes in parts of four counties – Berkshire, Hampshire, Oxfordshire and Wiltshire. It encompasses one of the largest and least developed tracts of chalk downland in southern England. The AONB has a relatively low population, but because its boundary skirts around larger urban areas, such as Swindon, Reading and Basingstoke, a large number of people live within easy access.
This rolling chalk downland stretches west from the River Thames in a broad arc to the south of Swindon, including the Berkshire and Marlborough Downs, with a steep scarp slope looking out over the Vale of White Horse, and then sweeps south and east to include the Vale of Pewsey and the North Hampshire Downs before circling round Newbury back to the Thames.
Although the downs are termed ‘hilly’, they don’t rise to any great height, which makes the walks here suitable for a wide range of abilities. Nevertheless, the walks in this guide take in not only the highest chalk hill in England (and highest point in Berkshire), Walbury Hill (297m; Walk 26), but also the highest points in three other counties – Milk Hill in Wiltshire (295m; Walk 21), Pilot Hill in Hampshire (286m; Walk 27) and Whitehorse Hill in Oxfordshire (262m; Walk 11).
This classic chalk landscape has been shaped by human activity for thousands of years, and some of the walks follow ancient trackways past some stunning historic sites, such as Avebury (one of the largest henge monuments in Britain; Walk 18), the 3000-year-old stylised galloping figure of the Uffington White Horse (Walk 11), impressive Neolithic long barrows, Bronze Age barrows and Iron Age hill forts. Take time to admire the views and ponder why and how our ancestors created these iconic features.
But that’s not all. The walks allow you to explore parts of the Ridgeway National Trail, the Kennet and Avon Canal, peaceful riverside locations and picture-postcard villages with thatched cottages, historic churches and cosy pubs.
The North Wessex Downs offer an abundance of peace and tranquillity – here you can listen to skylarks singing over the open chalk grassland and the wind gently rustling through the trees; be dazzled by the myriad of flowers and butterflies; in late autumn see flocks of fieldfares and redwings feed along the hedgerows; and enjoy the views across the gently rolling chalk landscape that has inspired many a writer, poet and artist over the years.
For more information on this beautiful area, see www.northwessexdowns.org.uk.
Geology
The geology of the North Wessex Downs tells the story of the seas that once covered southern England and the sediments that were laid down at that time. The predominant feature – one that forms the rolling contours of the downs – is a thick layer of Upper Cretaceous chalk (99–65 million years old), composed of incredible numbers of tiny fossil skeletons of algae, called coccoliths. Associated with the upper (white) layer of chalk are horizontal bands of irregular silica concretions, known as flints. These also occur in profusion in the jumbled deposits of weathered chalk, known as ‘clay-with-flints’. When struck, flint breaks with a shell-shaped fracture, leaving very sharp edges, and our Stone Age ancestors used flints to make arrowheads and hand axes. Being a very hard-wearing rock, flint has also been widely used as a building material.
Upper (white) chalk with layer of flint
Underlying the porous chalk is an impervious layer of Gault Clay laid down during the latter part of the Lower Cretaceous period (145–99 million years ago). This junction between the clay and chalk gives rise to the spring-line along the northern edges of the downs, where water that has seeped through the chalk is forced to the surface to form springs.
A natural process of patchy and irregular hardening within the sandy beds that overlay the chalk produced blocks of tough sandstone that are more resistant to erosion. These are the famous sarsens, known locally as Grey Wethers (from a distance they are said to resemble sheep – a ‘wether’ being a castrated ram). Sarsens were used in the construction of the stone circle at Avebury and the Neolithic long barrows at West Kennett (Walk 18) and Wayland’s Smithy (Walk 11); a great number of sarsens can be seen in their natural state at Fyfield Down National Nature Reserve (Walk 17).
Throughout the last 2.6 million years (the Quaternary period) Britain has been subject to periods of glaciation separated by warmer interglacial periods (the last glacial period ended about 12,000 years ago). There is no evidence to suggest that the North Wessex Downs were ever covered in ice, but the area did suffer periglacial conditions that allowed the formation of dry valleys, or coombes, in the chalk plateau. The coombes were formed by erosion, as water flowed over the surface of the chalk during cold periods