Scotland’s Longest Glen
The Great Glen runs 104km (65 miles) across the Scottish Highlands from Fort William to Inverness.
“The series of 8 locks known as Neptune’s staircase is the longest staircase lock in Britain, and is found in Banavie, just outside Fort William (postcode PH33 7LY)”
This stunning glen cuts straight across the mountainous scenery of the highlands, forming a natural motorway for walkers, cyclists and paddlers. It takes you from the west coast of the UK across to the east coast. It takes between 5 and 6 days to walk the Great Glen. Paddlers will have a trip to remember with the route taking in Loch Lochy, Loch Oich and Lock Ness.
But how was this amazingly straight glen formed?
The answer lies in Geology. The Great Glen follows an enormously long natural fault known as the Great Glen Fault. A fault is a break in the earth’s crust where movement takes place. In the case of the Great Glen the land masses on either side have been sliding past each other in a south-westerly to north-easterly direction. This fault is similar in style to that of the famous San Andreas fault in California.
How much has it moved and when?
It is believed that the rocks in the North West Highlands (on the North side of the fault) have moved at least 100 km relative to those in the Grampian Mountains (on the south side of the fault). The most significant movement occurred between 430 and 400 million years ago. There doesn’t appear to be any significant movement along the fault today, although there were a number of minor earthquakes in the Inverness area a century ago.
Why is the Great Glen so deep?
Loch Ness is 230m deep, meaning the lake bed is well below sea level. As fault movements occurred along the Glen the rock became pulverised and smashed. This meant it was easily eroded by water and glacial ice. The Glaciers travelled down the glen scouring out the broken rock and creating the deepest lochs in Scotland. Part are the evidence for this is the complete lack of islands in the Great Glen. Take a drive along the A82 and see for yourself.
The A82 road along the Great Glen skirts the banks of Loch Lochy, Loch Oich and Loch Ness, and is recognised as one of the most scenic drives in Britain.
For more on attractions and activities in the Great Glen area visit www.highland-glens.co.uk.