Loch Ness was created about 20,000 years ago during the last glacial period which ended about 10,000 years ago. The loch forms part of the Great Glen, a long transcurrent fault line. Aligned northeast to southwest, the Great Glen Fault extends further southwest in a straight line through Loch Linnhe and the Firth of Lorne, and then on into northwestern Ireland, directly through Lough Foyle, Donegal Bay and Clew Bay. To the northeast the fault becomes obscured by the effects of Mesozoic rifting to the north of Shetland. Further reading about the Great Glen can be found here at Scottish Geology and a particularly good map shows the rock types and straightness of the fault line. The fault is over 400 million years old but is now mostly inactive. Some moderate tremors have been recorded over the past 150 years and we have experienced one such event ourselves since we live right on this fault line!
The deep trough of the Glen was carved out of the weakened rock by massive glaciers and melt water. As the glaciers retreated large amounts of rock debris sand and gravel were left behind and The Meall Na Sroine Stone is one such boulder left perched on the hilltop by this process.
Known as glacial erratics, these rocks are sometimes carried for very long distances and often have a lithology different than the bedrock upon which they sit, making them ideal indicators of former ice movement.
The Meall Na Sroine Stone may not have travelled far since it appears to be of the same material as the surrounding rock. It isn’t particularly big or beautiful but it rocks! This boulder has been left by the ice such that it can be rocked to and fro very easily by one person. A word of warning if your name is MacDonald. This rocking stone is reputed to fall on any member of the Clan MacDonald!!
To get to the cache site you can park at Alltsaigh at N 57º 14.208´ W 004º 33.448´. Please do not obstruct any access.
The name Alltsaigh is taken from the name of the burn which runs into Loch Ness at this point. Local folklore suggests that the burn was named after the last wolf in Scotland, shot here in the 19th century.
Follow the track through the gate and at the first junction turn left. Cross over the bridge and continue along the track. At the second junction turn right and at the third, turn left and keep going until have a good view of Loch Ness on your left. A little further along at N 57º 13.945´ W 004º 34.285´ you will come to an almost treeless slope on the right of the track. Leave the track here and head up the hill towards a clump of birch trees to the left of a single birch on the rocks. Once at the trees follow your GPS to the cache site. When you get near the cache site the stone will be very obvious.
To claim this cache, you must do three things:
1) Post a photo of yourself at the boulder with your GPS clearly in view.
2) Estimate the mass of the boulder in kilograms. You will have to work out the volume of the boulder in cubic metres first, by "measuring" it on site. The boulder is roughly spherical so you will have to find the formula for the volume of a sphere. For each cubic metre of rock, the mass is about 2.75 tonnes.
3) What is another name for a rocking stone? (It sounds Scottish)
E-mail the answers to us via our profile. If we do not receive the answers and/or a photo is not posted, you may have your log deleted.....
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