20,000 years ago Scotland, like much of the Northern Hemisphere was blanketed by a great ice sheet, over 4000ft thick in places; and the effect on our landscape of this event is huge. Ice ages occur in part because of astronomical cycles, and over the course of the last two million years the ice has waxed and waned over Scotland. The last 10,000 years have been warm and ice free, but the legacy of the glaciers upon our scenery and history is incalculable.
For centuries the Parallel Roads of Glen Roy had baffled both scientists and myth-makers alike; and solving the puzzle would reveal an amazing picture of our geological past. Glen Roy, in Lochaber has three distinct, parallel terraces running the length of both sides of the valley; and it wasn’t until the mid 19th century did geologists realise that they were looking at ancients shorelines from a lake dammed back by huge glaciers. The understanding that Scotland was once glaciated opened up the study across the world; but it was here that scientists had their ah-ha moment.
