Botallack was a submarine mine with tunnels extending under the sea, in places for half a mile. Over its recorded lifetime the mine produced around 14,500 tonnes of tin, 20,000 tonnes of copper, and 1,500 tonnes of arsenic. An estimated 1.5 million tonnes of waste would have been dug up with the minerals. It is unclear how far back mining activity goes in this location. Early records date from the 1500s. Some archaeological evidence points to mining here in the Roman era or even as far back as the Bronze Age.