The Seven Stones Reef is a rocky reef nearly 15 miles (24 km) to the west-north-west (WNW) of Land's End, Cornwall and 7 miles (11 km) east-north-east (ENE) of the Isles of Scilly.
They rise out of deep water and are a navigational hazard for shipping with seventy-one named wrecks and an estimated two hundred shipwrecks overall.
The most infamous is the Torrey Canyon in 1967, which was at that time the world's costliest shipping disaster, and to date, still the worst oil spill on the coast of the United Kingdom.
It is permanently anchored in 40 fathoms (73 m) and is 2.5 miles (4.0 km) north-east (NE) of the reef.
It has been in situ almost continuously, except when it has dragged its anchor, removed for safety during the Second World War or for a few days while the Torrey Canyon was bombed by the military.