(c) Martyn Farr - Divers carry remote underwater flash guns to illuminate this image, taken in what is probably the world's biggest underwater tunnel, Weebubbie Cave beneath the remote Nullarbor Plain of western Australia.
Myriads of ancient tunnels all over Europe lead nowhere and baffle everyone? Well of course they do. The goblins dug deeper and collapsed the cave entrances before we could conceive of thermal imaging and power tools.
Isle of Staffa – an inner island of the Hebrides, which stretches along the coast of Scotland. Fingal Cave, located in the south and which is part of his reserve, was named in honor of the hero and Irish Gaelic epic giant Fingal