Brean Down Fort Brean Down Fort was built above sea level on the headland at Brean Down , south of Weston - super - Mare , Somerset , England . The site has a long history , because of its prominent position . The earliest recorded settlement is from the Early to Middle Bronze Age . The current buildings were constructed in the 1860s as one of the Palmerston Forts to provide protection to the ports of the Bristol Channel , and was decommissioned in 1901 . During World War II it was rearmed and used for experimental weapons testing . The site has been owned by the National Trust since 2002 , following a £431 , 000 renovation project , as part of its Brean Down property and is open to the public . The fort was used as a location for filming of the second episode , " Warriors " , of the BBC television drama " Bonekickers " . Bronze Age to Roman . The earliest record settlement is from the Early to Middle Bronze Age . It is now on an exposed cliff as the land has been eroded by the sea . Bronze Age artefacts from the site include pottery and jewellery . Most of the finds are now in the Museum of Somerset in Taunton . The presence of a probable roundhouse has also been detected . The site has also produced Roman gold and silver coins of the emperors Augustus , Nero , Drusus and Vespasian and a cornelian ring . Palmerston Fort . Brean Down Fort forms part of a line of defences , known as Palmerston Forts , built across the channel to protect the approaches to Bristol and Cardiff . It was fortified following a visit by Queen Victoria and Prince Albert to France , where they had been concerned at the strength of the French Navy . The Royal Commission on the Defence of the United Kingdom , under direction of Lord Palmerston , recommended fortification of the coast . Brean Down Fort formed part of a strategic coastal defence system covering the channel between the mainland and the islands of Steep Holm and Flat Holm . Four acres of land at the end of Brean Down were requisitioned in 1862 , with construction beginning in 1864 and completed in 1871 . The fort was originally armed with seven rifled muzzle - loading guns , which were among the last of this type to be made at the Woolwich Gun Foundry . These sited at three main gun positions , including W battery containing two guns on ' C ' pivots ( rotating around a reused Georgian cannon set upright in the ground ) . Each gun weighed 7 tons and had a charge of gunpowder able to fire a Palliser shot at per second . This could pierce of armour at . It was proposed to replace the guns with larger versions in 1888 but this was never put into action . It had a large , underground , main gunpowder magazine , 15 feet ( 4 . 5 m ) by 18 feet ( 5 . 5 m ) by 20 feet ( 6 . 1 m ) high . The fort was staffed by 50 officers and men of the Coast Brigade , Royal Artillery , but no shots were ever fired in action . The end of the fort ' s active service came at 5 am on 6 July 1900 when the No . 3 magazine which held 3 tons ( 3 tonnes ) of gunpowder exploded . An inquiry found that Gunner Haines had fired a ball cartridge down a ventilator shaft causing the explosion , after being put on a charge for returning late to barracks , however this explanation has been challenged . The wall separating the fort from the moat on the south west corner was demolished and wreckage thrown up to . No one knew why the gunner had blown up the fort , but it has been speculated that it was an act of suicide . The cannons were hauled away by traction engine s . It was then used as a café , owned by the Hillman family from at least 1907 until sold in 1936 to the ' bird sanctuary people ' . World War II . On the outbreak of World War II the fort was rearmed with two ex - naval guns and two searchlights as a Coastal artillery battery . The site was also used as a test launch site for rockets and experimental weapons . Two gun positions were built to mount the ex - naval guns in their turrets . These were later protected with a " plastic " anti - aircraft roof . One position was built over the ruins of the old west battery and the other partly obscures the north west battery . The barrack blocks were converted and the windows partly blocked to reduce the effects of blast . Several other associated structures , including searchlight batteries for illuminating seaborne targets , a command post and the barracks for the garrison were built outside the original Palmeston fort . The site was manned by 365 and 366 Coast Batteries RA of 571 Coast Regiment in 1942 . Several experimental weapons were trialled at Brean , by the Admiralty ' s Directorate of Miscellaneous Weapons Development , based at HMS Birnbeck . The only evidence being a short length of launching rail , designed to launch a bouncing bomb . Some of the better known weapons trialled were the seaborne Bouncing bomb designed specifically to bounce to a target such as across water to avoid torpedo net s , Anti - submarine missile AMUCK and the expendable acoustic emitter ( designed to confuse noise seeking torpedoes ) .