Staffa, named ‘Stave’ or ‘Pillar Island’ by the Vikings, lying 6 miles (10 km) west of Mull, was formed volcanically at the same time as the Giant’s Causeway, cooling into mainly hexagonal black basalt columns. Cliffs rising to 131 feet (40 m) are riddled with caves, the most famous of which is Fingal’s Cave at Staffa’s southern tip, named after legendary Irish hero, Finn MacCool.