of earth ramparts are still visible, forming a semicircle that encloses an area of adjacent to the cliff edge. The enclosure has a single entrance at the east side with inturned defensive banks. Archaeological investigations have shown that both ramparts are strengthened by dry stone walling; the inner rampart also has timber strapping. The fort was destroyed by fire in around 400 BC, although the area was probably used as a settlement until the Roman invasion of Britain in the 1st century AD. The site is well preserved despite quarrying of the area during the 17th to early 20th centuries, as well as military training exercises during the 20th century. The remaining earthworks have been designated a Scheduled Monument, and the site is owned by the National Trust. Since 2009, the trust has been removing trees, scrub and bracken from the site, as the roots damage the earthworks. Animal burrows are another threat, and footpath erosion from visitors is also a problem, as the Sandstone Trail cuts across the earthworks. There is another Maiden Castle which is an Iron Age hill fort 2.5 kilometres (1.6 mi) south west of Dorchester, in the English county of Dorset. Anglo-Saxon and Norman The name "Bickerton" is Anglo-Saxon in origin, and relates to bees. A township was recorded in the Domesday survey, which was found "waste", or devastated, at the time of the survey, in common with many nearby townships. This is usually considered to be a consequence of William I's suppression in 1069–70 of uprisings in north-west Mercia. The township included half a league (about mile) of woodland, perhaps located on the hills. 17th–19th century Copper mining at Bickerton was first recorded in 1696. The mine was owned by the Egerton family of Oulton, with eight miners being employed between 1696 and 1698. There were six shafts, one of which was deepened to in 1807. The mines were worked intermittently until 1906. A rare remnant of this local industry is a disused mine engine house chimney in red sandstone, which stands by the A534 at the foot of the northerly hill near Gallantry Bank. The flue of a pumping engine that was used to drain the mine, it dates from the early 19th century and is a grade-II-listed building. The remains of adjacent mining buildings were still standing in around 1920. The Copper Mine public house at nearby Broxton displays mining equipment and