At the jetty on Iona turn left and walk along the road by Martyrs Bay. On the shore you can see a glacial erratic boulder sitting on top of Torridonian sandstone. It was transported by ice across the Sound of Iona. The Torridonian sandstone beds can be seen to be almost vertical at this locality.
Walk further along the road and where it turns right then turn off onto the sandy beach at Traigh Mhor.
For more information on this geological walk click here to see the informative Mull Historical and Archaeological website.
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