Bow Fiddle Rock, Scotland. This natural sea arch, known as Bow Fiddle Rock, is just off the coast at Portknockie on the Moray Firth, in north-eastern Scotland. It is some 15 metres tall and is formed of quartzite rock dating from around 650 million years ago. It is so named because the thin side of the arch resembles a fiddler's bow. The arch formed as wave action eroded a passage through the rock.