Pictured: These early-medieval stone graves near Heysham, Lancashire, may be familiar from a Black Sabbath LP cover. For Sheila Rock they evoke many subsequent deaths, including those of the Chinese cockle-pickers in nearby Morecambe Bay in 2004. "When the water comes in, anyone caught gets enveloped by the sea." Viking remains are also found near where St Patrick is said to have landed. "It's hugely atmospheric"