Question: What is the name of the Cornwall heritage property that was a development of pagan Celtic memorial stones ?

text: List of English Heritage properties
Cornwall

English Heritage is a registered charity that manages the National Heritage Collection. This comprises over 400 of England's historic buildings, monuments, and sites spanning more than 5,000 years of history. It has direct ownership over some historic sites and also liaises with private owners of sites that are managed under guardianship arrangements. The following is a list of English Heritage properties containing links for any stately home, historic house, castle, abbey, museum or other property in the care of English Heritage.
Name Type Date Condition Notes
Ballowall Barrow Megalithic tomb Neolithic Remains A prehistoric funerary cairn ( chambered tomb ) situated on the cliff top at Ballowall Common , near St Just . It was first excavated in 1878 by William Copeland Borlase when it was discovered under mining debris . The site today is a confused mix of original and reconstructions introduced by Borlase
Carn Euny Ancient Village Village and Fogou Iron Age Remains A Romano-British village near Sancreed , on the Penwith peninsula , with considerable evidence of Iron Age settlement as well . Carn Euny is best known for the well-preserved state of the large fogou , an underground passageway , which is more than 20m long
Chysauster Ancient Village Village Iron Age Remains A Romano-British village of courtyard houses , believed to have been constructed and occupied between 100 BC and 400 AD ; it was primarily agricultural and unfortified and probably occupied by members of the Dumnonii tribe . The village included eight stone dwellings , arranged in pairs along a street , each with its own garden plot
Dupath Well Wellhouse 1510 Complete A wellhouse constructed over a local spring . Built of Cornish granite ashlar , it was probably built by the Augustinian canons of the nearby priory of St Germans , to whom the site belonged
Halliggye Fogou Fogou Iron Age Remains Located on the Trelowarren estate near Helston , it consists of a long narrow tunnel leading to three sectioned chambers , and a window-like entrance which was dug in Victorian times by supposed treasure hunters . It is the largest and best-preserved of several mysterious tunnels associated with Cornish Iron Age settlements
Hurlers Stone Circles Stone circle Neolithic Remains A group of three stone circles . The site is half-a-mile west of the village of Minions on the eastern flank of Bodmin Moor . The circles have diameters of 35m , 42m and 33m . The two outer stone circles are circular , the middle and largest stone circle , however , is slightly elliptical
King Doniert 's Stone Standing Cross 9th century Remains Consists of two pieces of a decorated 9th-century cross . The inscription is believed to commemorate Dungarth , King of Cornwall who died around 875 . The site also includes an underground passage and chamber
Launceston Castle Castle 11th century Ruins A Norman motte and bailey castle raised by Robert , Count of Mortain , half-brother of William the Conqueror . It became the administrative headquarters for the powerful Earls of Cornwall . The castle remained with little development , apart from an inner keep added in the 12th century . During the 13th century , Richard , Earl of Cornwall , a younger brother of Henry III began to rebuild the castle in stone
Pendennis Castle Device fort 1539 Partly complete One of Henry VIII 's Device Forts . Built to guard the entrance to the River Fal on its west bank , near Falmouth . St Mawes Castle is its opposite number on the east bank and they were built to defend Carrick Roads from the French and Spanish threats of future attack . The castle comprises a simple round tower and gate enclosed by a lower curtain wall
Penhallam Manor House 12th century Ruins The site of a former medieval manor house surrounded by a protective moat , abandoned during the mid-14th century . Penhallam is one of only four such moated medieval manor sites in Cornwall and it consists of a quadrangle of buildings around a central courtyard
Restormel Castle Castle 12th century Ruins Situated on the River Fowey near Lostwithiel , it is one of the four chief Norman castles of Cornwall . The castle is notable for its perfectly circular design . Although once a luxurious residence to the Earl of Cornwall , the castle became ruined in the years after
St Breock Downs Monolith Monolith Neolithic Remains A 5m high prehistoric standing stone located near St Breock
St Catherine 's Castle Device fort 1530s Remains A small fort commissioned by Henry VIII to protect Fowey Harbour . A twin battery of 64-pounder guns was added on a lower terrace in 1855 . One emplacement was modified in the Second World War to mount a 4.7 naval gun , but was later removed to restore the Victorian gun races
St Mawes Castle Device fort 1540s Remains St Mawes Castle and its larger sister castle , Pendennis , were built as part of a defensive chain of fortresses by Henry VIII to protect the south coast of Cornwall , England , United Kingdom
Tintagel Castle Castle 13th century Ruins A medieval fortification located on the peninsula of Tintagel Island . It saw settlement during the Early Medieval period , when it was probably one of the seasonal residences of the regional king of Dumnonia . In the 13th century , during the Later Medieval period , after Cornwall had been subsumed into the kingdom of England , a castle was built on the site by Richard , Earl of Cornwall
Tregiffian Burial Chamber Megalithic tomb Neolithic Remains A Neolithic or early Bronze Age chambered tomb , comprising an entrance passage , lined with stone slabs , leading to a central chamber , located near Lamorna in west Cornwall
Trethevy Quoit Megalithic tomb Neolithic Remains A well-preserved megalithic tomb located near St Cleer . It is known locally as the giant 's house and stands 2.7m high , and consists of five standing stones capped by a large slab