The castle stands on a narrow promontory, which determined the layout of the defences. The castle is named for the Cantilupe family, the first feudal tenants of the castle. Unfortunately, the castle builders did not take into account the possibility of coastal erosion.
Candleston stands at the eastern edge of what is now Europe's largest sand dune system. The castle had scarcely been built before the surrounding area began to be submerged by coastal sands.
The castle itself was saved from immersion under the sand by dint of its elevated position, but the surrounding area was largely covered, leading to the eventually abandonment of Candleston.
Less than a mile away across the River Ogmore are the substantial remains of Ogmore Castle.