Beech Bottom Dyke, is a large ditch running for almost a mile at the northern edge of St Albans, Hertfordshire flanked by banks on both sides. It is up to wide, and deep, and it can be followed for three quarters of a mile between the "Ancient Briton Crossroads" on the St Albans to Harpenden road until it is crossed by the

Thameslink Thameslink is a 24-hour main-line route in the British railway system, running from , , , and via central London to Sutton, , , Rainham, , , , and . The network opened as a through service in 1988, with severe overcrowding by 1998, carrying ...

/ Midland mainline railway at

Sandridge Sandridge is a village and civil parish between St Albans and Wheathampstead in Hertfordshire, England. History The original name was "Saundruage" meaning a place of sandy soil serviced by bond tenants. The earliest recorded mention of Sandri ...

. Beyond the railway embankment it continues, to finish just short of the St Albans to Sandridge road. This part is not accessible to the public. It was constructed towards the end of the

Iron Age The Iron Age is the final epoch of the three-age division of the prehistory and protohistory of humanity. It was preceded by the Stone Age ( Paleolithic, Mesolithic, Neolithic) and the Bronze Age ( Chalcolithic). The concept has been mostl ...

, probably between 5 and 40 AD. This, and other similar earthworks in the district, may have been built by the powerful Celtic tribe established in this area, the

Catuvellauni The Catuvellauni (Common Brittonic: *''Catu-wellaunī'', "war-chiefs") were a Celtic tribe or state of southeastern Britain before the Roman conquest, attested by inscriptions into the 4th century. The fortunes of the Catuvellauni and their ...

, probably by King Cunobelinus to define areas of land around their tribal centre at

Verlamion ''Verlamion, or Verlamio, was a settlement in Iron Age Britain. It was the centre of Tasciovanus' power and a major center of the Catuvellauni from about 20 BC until shortly after the Roman invasion of AD 43. Its location was on Prae Hill, 2& ...

- the predecessor of the Roman city of

Verulamium Verulamium was a town in Roman Britain. It was sited southwest of the modern city of St Albans in Hertfordshire, England. A large portion of the Roman city remains unexcavated, being now park and agricultural land, though much has been built upon ...

. Beech Bottom Dyke is thought to have originally been part of a defensive system for a Belgaic settlement. Other defences are the Devil's Dyke and another ancient earthwork known as " The Slad". These may have created a defensive earthwork running from the River Lea to the

River Ver The Ver is a long chalk stream in Hertfordshire, England. It is a tributary of the River Colne. Course The source is in the grounds of Lynch Lodge, Kensworth Lynch on the west side of the A5 trunk road and stays on the west side for som ...

enclosing a very large area. Image:Beech Bottom Dyke (1).jpg, Photograph of the Dyke Image:Beech Bottom Dyke (2).jpg, Photograph of the Dyke Image:Beech Bottom Dyke (3).jpg, Photograph of the Dyke

References

History of Hertfordshire History of St Albans Iron Age sites in England Archaeological sites in Hertfordshire Ancient dikes Buildings and structures in St Albans Linear earthworks {{UK-archaeology-stub