Geology
Around 60 million years ago, the region was volcanically active, with Ben More being the remnant of a volcano, and it was in this period that the famous rock formations of Staffa and the basaltic columns of "The Castles" on Ulva came into being. The lava flows are known as the "Staffa Magma Type member" and can also be seen on Mull at Carsaig, Ardtum, and near Tobermory on its east coast. They are particularly rich in silica.
Read more about this topic: Ben More (Mull)