The sediments here are known as Middle Old Red Sandstone and are made up of sandstones, mudstones and siltstones. Battered by millennia of wave action from the sea, the rocks have worn away in this area to form a sea arch. Eventually, the ‘roof’ of the archway will collapse to form a sea stack. This familiar geological feature can be seen in many places in Orkney, the most famous being the Old Man of Hoy.
Holm of Faray Natural Arch © George Brown
