A chalk and gravel hill on the Fenland edge with a story of ancient rivers and ice sheets.
Zoom in to the Google Map to find the points of interest.
Maidscross Hill is a heathland area with old chalk and gravel workings. It is a Local Nature Reserve and SSSI designated for its wildlife value, particularly plant life. The patches of chalky and sandy topsoil are habitat for an interesting range of Breckland species, some rare. The site gives views over RAF Lakenheath airfield and the western Brecks landscape.
Old Gravel pits.
The hill is founded on an upstanding body of Cretaceous chalk. It is a glacially-eroded and isolated bit of the chalk scarp landscape which stretches from north Norfolk down to the Chilterns and beyond. Chalk rubble lies close to the surface, particularly near the top of the hill. It can sometimes be seen here in the sides of freshly-cut ditches and trenches. Periglacial frost action in the subsoil during the last ice age churned the chalk/sand interface into interesting patterns. These were once visible in ditches and quarries on the hill.
[Image from ’The Geology of parts of Cambridgeshire & Suffolk’ by Whitaker et al (1891)]
Layers of sand and gravel cover the chalk. They are part of a complex geological story. As well as local flint, they contain pebbles of Bunter quartz and quartzite, originally brought to the area from the Midlands by the now-vanished Bytham River, which passed through here over ½ million years ago. The course of the Bytham River was destroyed by the advancing Anglian ice sheet when it occupied the Fenland basin about 450,000 years ago. Some remaining patches of river gravels were later reworked by meltwater rivers draining another ice sheet that entered the Fenland basin, perhaps 160,000 years ago, and were deposited at Maidscross Hill as part of a delta. Geological structures indicate that the water flowed towards the south-east.
A vanished landscape – conjectured course of the Bytham River. [Image by Stephanie Hartick]
Flint and quartzite pebbles are brought to the surface by rabbits.
The soils of Maidscross Hill are sandy, with much chalk rubble close to the surface. This gives rise to an interesting variety of plants of both calcareous and acidic heathland, with rarities including Sand Catchfly, Sickle Medick and Breckland Thyme. The site is also noted for its ground beetles (carabids). Several rare species typical of dry, open, disturbed ground have been found in the gravel pit at the bottom of the hill.
Brecks heathland plants thrive on the open disturbed ground.
Biting stonecrop, an attractive plant of thin, dry soils.
One of the panels prompting thought about links between geodiversity and biodiversity.
A local wall recaps the geological story on Maidscross Hill. Seen here at the entrance to Lakenheath Hall (grid ref TL 714 835), brown Bunter quartzites are overlying blocks of chalk clunch.
Maidscross Hill gives panoramic views over RAF Lakenheath airfield. A century ago it was a great rabbit warren developed on an open expanse of sandy heathland. The surface layers were wind-blown coversand, in places forming semi-mobile dunes. Some similar dunes survive at nearby Wangford Glebe, although they are not open to visitors.
Relict dunes at Wangford Glebe.
The site is public access land marked on Ordnance Survey Explorer map no.228 ‘March & Ely’ (c. TL 723 826). The car park is at the far end of Cemetery Road. There are public information panels about Brecks heritage and links between soils and wildlife.