Most of the island of Eigg consists of a Tertiary lava plateau which was thrust up as a sheet over younger rocks from volcanoes on Rum and Skye over 50 million years ago.
In the north of the island and on the Sgurr this basalt is exposed as dramatic cliffs, home to eagles and ravens, and in places there are outcrops of hexagonal basalt columns just as spectacular as those at the Giant’s Causeway and Fingal’s Cave.
One effect of this thick basalt sheet has been to protect the younger, softer rocks beneath from erosion by ice and water and as a result younger Triassic limestones are now exposed along the west coast.
We made a memorable coastal walk starting on a rainy morning at the dispersed settlement of Cleadale where a number of families still practise traditional crofting, along with other occupations such as organic gardening, running bed-and-breakfasts, teaching in the local school and so on.
From Cleadale we followed a lane down past the beautifully restored St Donnan’s church, dedicated to the 7th century saint who first brought Christianity to Eigg, to the sands of Laig Beach – completely empty of visitors when we set out to follow the coast northwards, with calls of ringed plovers and oystercatchers the only sounds to be heard.
Between Laig Beach and the famous Singing Sands extensive strata of limestone are exposed on the beach and coastal slopes. The limestone meant that the slopes were full of colourful marsh, spotted, frog and butterfly orchids and down below we could see stretching out to sea several spectacular Basalt Dykes, where lines of lava had been thrust up from the ancient volcanoes through cracks in the overlying rocks.
As the weather cleared for lunch we reached the Singing Sands whose white quartz sand grains reputedly ‘sing’ in dry windy weather, but much of the sand had disappeared last winter in a particularly severe storm.
Woodland is surprisingly abundant on Eigg, including a recent Sitka Spruce plantation, an arboretum of exotic trees and shrubs around the Lodge, the former home of wealthy owners of Eigg, built in 1924 by Lord Runciman, and the native Atlantic hazel woods which grow on the steep slopes under the basalt cliffs on the east coast and above Cleadale. Recent study of these woods has shown that they are truly ancient rain forests, home to a great diversity of lichens, mosses, liverworts and fungi. The biggest problem is getting into them in summer through a sea of shoulder-high bracken and brambles into the dense tangle of hazel branches, and getting out again unscathed.