The Pembrokeshire Coast National Park is one of the most protected stretches of shoreline in Britain - cliffs, limestone arches, seabird colonies, a famous coastal path. Inside it, fenced off and active 44 weeks a year, sits 6,000 acres of working tank range. Castlemartin has been firing high-velocity rounds into its limestone bluffs since 1938. Hikers see the warning flags from the coast path. Locals know the dates of the firing notices. Out at sea, a shifting exclusion zone reaches as far as 12 nautical miles offshore when the heavier ammunition is in use. It is a strange place: a working army range inside a national park, an extreme noise inside extreme quiet.
The Ministry of Defence built Castlemartin in 1938 on a mix of deserted and inhabited farmland and on parts of what had been the Cawdor Estate. The Royal Armoured Corps wanted somewhere big enough to run tank gunnery without endangering British villages. The South Pembrokeshire headland - flat, sparsely populated, with the sea taking the overshoot - was ideal. After the Second World War the army left and the land returned briefly to agriculture. The reactivation came in 1951 when the Korean War began. From that point Castlemartin has been a working range almost continuously, with its byelaws revised in 1942, 1986, and at intervals since.
The strangest chapter began in May 1961. The newly reactivated West German army needed somewhere to train its tank crews, and the British Army of the Rhine's main range at Bergen-Hohne was crowded. A NATO agreement signed in Paris allowed the Bundeswehr to use Castlemartin's 5,000 acres. For 35 years - until October 1996 - German tank units rolled through Pembrokeshire on a regular cycle. Locals got used to the sight: German tank crews in the pubs of Tenby, Leopard tanks training across Welsh fields, signs in two languages around Merrion Camp. The arrangement ended only after German reunification opened up new training ground in the former East Germany. The Wales Online headline ran years later: "When German troops and tanks invaded Wales."
Live fire on a tank range is dangerous work, and the danger has costs. In May 2012, Ranger Michael Maguire of the 1st Battalion, The Royal Irish Regiment was killed when a stray round struck him in the temple while he rested in what was supposed to be a safe area, helmet and body armour removed. The same machine-gun fire was later judged to have put civilians on neighbouring beaches at risk. His unit was preparing for deployment to Afghanistan. On 14 June 2017 Corporals Matthew Hatfield and Darren Neilson of the Royal Tank Regiment died inside their Challenger 2 when the tank's main gun failed during firing. A bolt vent axial seal had not been fitted; hot gases vented back into the turret and ignited charges stored loose inside. Two crewmen survived the explosion and fire; their two friends did not. The coroner found the cause to be a manufacturing oversight - a hazard that had not been adequately considered when the gun was built. On 4 March 2021, Sergeant Gavin Hillier of the 1st Battalion, Welsh Guards died during a live firing exercise. Each death prompted a service inquiry; each name is now part of the range's record.
Castlemartin sits inside the Pembrokeshire Coast National Park and within a Site of Special Scientific Interest. The combination feels contradictory but is not unique - large parts of the British military estate happen to be ecologically valuable precisely because they have been kept undeveloped for military reasons. The Castlemartin grasslands contain fossils, rare flora, and some of the most dramatic limestone features on the coast: the Green Bridge of Wales, the deep fissure called Huntsman's Leap, and the offshore stacks known as Stack Rocks. St Martin's Chapel, a medieval building inside the range, was restored from 1901 to 1903 by Lady Victoria Alexandrina Lambton, daughter of the 2nd Earl Cawdor, with her husband Lt Col Francis Lambton. The chapel was listed Grade I in February 1996. A Celtic cross stands in the churchyard, erected in 1909 by Clarke of Llandaff.
Defence Training Estate Pembrokeshire took over administration in 1999 and now manages Castlemartin as the largest single component of its Welsh holdings. The estate also runs the air-defence range at Manorbier southwest of Tenby, the Penally Training Camp just outside Tenby, and the Templeton Dry Training Area south of Narberth. The range towers on Range Two and Range Five were designed for the army of the 1970s; the first replacement, on Range Two, was commissioned in 2022. NATO units rotate through. The Queen's Dragoon Guards ran Exercise Pashtun Tempest here in 2014 as their final preparation for the last British Afghanistan tour, putting Husky and Foxhound armoured vehicles through five days of intense use. The range stays active; the firing notices keep getting published; the limestone keeps taking the rounds.
Castlemartin sits at 51.63 N, 4.98 W on the south Pembrokeshire coast, between Freshwater West and Stackpole. Best viewed at 1,500 to 3,000 feet on non-firing days, with the limestone coastline of the national park and the offshore stacks visible. Active firing zones include coastal exclusion areas extending 3 to 12 nm offshore depending on the weapon in use - check NOTAMs and the published firing notice before any low overflight. Nearest aerodromes: Haverfordwest (EGFE) just north, Pembroke (military, restricted), Swansea (EGFH) further east. The MOD prohibits unauthorised access by air or ground during active firing periods.