in fossils that include corals, seashells and crinoids, which supports the theory of the marine deposition of the rocks. 13 separate layers have been identified in the 'sand cliff' on the south side, the lowest five dating to the millennia of the last glaciation. History Human occupation dates back to the Beaker culture of the late Bronze Age. There is also evidence of an Iron Age hill fort and prehistoric barrows and field systems. There is evidence of a shrine dating from pre-Roman times, which was re-established as a Romano-Celtic Temple in the mid-4th century. According to at least one source, it is extremely likely this was succeeded by a small late-4th-century Christian oratory. Several Roman finds including gold coins of Augustus, Nero, and Drusus, two silver denarii of Vespasian and a Roman carnelian ring were found at the site during quarrying. Brean Down Fort was built on the headland between 1864 and 1871 on the recommendations of the 1859 Royal Commission. It was the most southerly of a chain of defences across the Bristol Channel, protecting the access to Bristol and Cardiff. Four acres of land at the end of Brean Down were requisitioned in 1862, with construction beginning in 1864 and completed in 1871. In the 1860s plans were laid for a deep-water harbour on the northern shore of Brean Down. It was intended that this harbour would replace Bristol as a port on embarkation for transatlantic crossings and the export of minerals and agricultural produce from the Mendip Hills and the rest of Somerset. The foundation stones of the pier were laid, but the project was later abandoned after a large storm destroyed the foundations. In 1897, following wireless transmissions from Lavernock Point in Wales and Flat Holm, Guglielmo Marconi moved his equipment to Brean Down and set a new distance record of for wireless transmission over open sea. In 1912 Brean Down was leased by the Royal Society for the Protection of Birds as a bird sanctuary, acquiring the shooting rights to stop others shooting on the promontory. On the outbreak of World War II, the fort was rearmed with two 6-inch (15-centimetre) ex-naval guns, and machine gun posts were built on the Down. Birnbeck Pier was taken over by the Admiralty in 1941 as an outpost of the Department of Miscellaneous Weapons Development (DMWD). It was commissioned as HMS Birnbeck, and was used for secret