The Runnel Stone (, meaning stone abounding in seals), or Rundle Stone, is a hazardous rock pinnacle about south of Gwennap Head, Cornwall, United Kingdom. It used to show above the surface at low water until a steamship struck it in 1923. Marks Current Runnelstone buoy A buoy currently marks the position of the Runnel Stone. Until May 2012 it was topped with a flashing light, a bell which peals with the movement of the waves and was also fitted with a whistle set in a tube, which emitted a moaning sound when there was a good swell running. This mournful noise could be heard clearly from Gwennap Head, drifting in from the sea, and added to the eerie atmosphere on the cliffs in foggy conditions. In a gale during the 1960s, the buoy became tangled in a drifting cargo ship's anchor line, and the buoy was towed into Mount's Bay. On 13 May 2012, the buoy was replaced by THV Patricia with a larger one, with a whistle to replace the bell. Day markers on Tol-pedn On the mainland, there is a pair of cone-shaped navigation markers on Gwennap Head, in line with the Runnel Stone buoy. These are day markers warning vessels of the hazard of the Runnel Stone. The cone to the seaward side is painted red and the inland one is black and white. When at sea the black and white one should always be kept in sight in order to avoid the submerged rocks nearer the shore. If the black and white cone is completely obscured by the red cone then the vessel would be directly on top of the Runnel Stone. The landmark was erected by the Corporation of Trinity House in 1821 – an event recorded on a plaque on the back of the black and white marker. Historic Beacons In 1795, following numerous petitions from mariners for dangers around Land's End to be marked by lights and beacons, Trinity House built a lighthouse on the Longships, and beacons on Wolf Rock and the Rundlestone. The latter, a bare wrought iron pole, was 'soon carried away by the sea'. In 1841, work began on erecting a replacement beacon (designed by James Walker, chief engineer at Trinity House). The process was one of 'great difficulty and danger': only a small portion of the rock protruded from the water, and landing by boat was only