rough seas are expected. The Institute has a plaque to Guy Gibson VC, leader of the Dambuster Raid, on the wall facing the harbour. Gibson was born in India, but saw Porthleven – his mother's home town, where his parents were married – as a home town as well. He visited there while on leave during the war, sometimes attending the Porthleven Methodist Church. His name is marked on the community's war memorial (he was killed in 1944) and a street (Gibson Way) is named after him. The harbour William Cookworthy acquired leases on the Tregonning Hill quarries and shipped china clay to his porcelain factory in Plymouth. In 1826, 150 tons of china stone and 30 tons of china clay were exported, and in 1838, 500 tons of china stone. By 1876, 970 tons were exported and in 1883, 1002 tons. Granite was also exported, from the quarries at Coverack Bridges and Sithney. Fifty-two fishing boats were built between 1877 and 1883, employing at times up to twenty people. They ranged in length from to and were built not only for Mount's Bay ports, but for others in the UK and in South Africa. Overnight on 12–13 December 1978, Police Constables Joseph James Childs and Martin Ross Reid of Devon and Cornwall Police were killed when their patrol car was swept into the harbour during a heavy storm. A stone memorial was erected on the south-facing harbour wall. Lifeboat Due to the prevailing westerly winds, it was easy for a ship under sail to be trapped in Mount's Bay and wrecked nearby. The Royal National Lifeboat Institution stationed a lifeboat at Porthleven in 1863. A boat house was built at Breageside, from where the boat was taken to the water on a carriage. The Agar Robartes was replaced by the Charles Henry Wright (named after the donor) in November 1882. A boat house on the west side of the harbour entrance was opened in 1894, with a slipway to ease launching. The station was closed in 1929, as the neighbouring stations at and had been equipped with motor lifeboats that could cover the whole bay. The slipway was dismantled and the boat house used as a store for a while. It has since become the Shipwreck Centre museum. Protected areas Three of the four Sites of Special Scientific Interest (SSSI) close to Porthleven, and the Geological Conservation Review (GCR)