The cave is completely formed by hexagonal basaltic pillars, similar and contemporary to those of the Giant's Causeway in Northern Ireland and the neighboring island of Ulbha. A lava flow 60 million years ago began to cool in hexagonal patterns which, starting from the surface, extended deep into the columns.
Its size, the arched ceiling and the mysterious sounds produced by the echoes of the waves make the natural formation look like a cathedral. The Gaelic name of the cave is Uamh-Binn, cave of the Melody. The cave has a large arched entrance and is flooded by the sea, but boats cannot enter.
Many local companies include a close pass on cruises between April and September. It is however possible to disembark on the island and walk to the cave: a row of fractured columns form a path just above the high tide level.
From the inside, the entrance seems to frame the sacred island of Iona.
Cave of Fingal: between Scottish and Norse suggestion
The cave was discovered by naturalist Joseph Banks in 1772. It became known as Fingal's Cave after the hero Fingal from a James Macpherson poem of the Ossian Cycle.
In Irish mythology Fingal is known as Fionn mac Cumhaill, who according to legend built a pavement between Ireland and Scotland. Composer Felix Mendelssohn visited the cave in 1829 and then composed Die Hebriden, inspired by the cave's strange echoes, which made it popular as a tourist destination.
Johannes Brahms also sang the Gesang aus Ossians Fingal, which is part of the Vier Gesänge for female choir, two horns and harp. An instrumental piece by Pink Floyd is called Fingal's Cave: written for Zabriskie Point, it was not included in the soundtrack of the film.
The playwright August Strindberg set some scenes from The Dream in a place called Fingal's Grotto in the cave, and the French writer Jules Verne also placed the ending of his novel The Green Ray in the cave. The cave also recurs in the verses of the Italian poet Eugenio Montale, who mentions it in the poem "Magenta Clouds..." contained in the sixth section of the poetic collection La bufera e other.
Other famous 19th-century visitors were Walter Scott, William Wordsworth, John Keats, Alfred Tennyson, the romantic painter William Turner who painted it in 1832, and Queen Victoria.