The sedimentary rocks which cradle Loch Ness are some of the oldest in the world. The sandstones were originally laid down in warm seas which then comprised Scotland. You would not have recognised the land masses at that time and, surprisingly, Scotland was probably located in the latitude where Australasia exists today.
As the continents drifted northwards at the speed of your growing fingernail [credit to Adrian Shine for this excellent description of the speed of continental drift) Scotland became squeezed into the dry centre of the super-continent Pangaea. By this time, 250 million years ago, the Great Glen side slip fault, which is home to Lochs Ness, Oich, Lochy and Linnhe, had already been created.
As Scotland crossed the equator it was the time of the dinosaurs and then as the continents began to break up and cluster around the north pole, the great ice ages began. Scottish mountains, which would have been Himalayan in size were gradually worn down to the stumps which you see today.
Scotland was still in the grip of the ice twelve thousand years ago, but the main advances were over and the land was beginning to rebound from being depressed into the mantle. The surface of Loch Ness would have been at a similar elevation to sea level, but detailed and thorough examination of the sediments at the northwest end of the loch show no evidence for any incursion of the sea since the last ice age.
Anything living in Loch Ness today must have arrived from the freezing North Sea up the River Ness after the final retreat of ice, ten to twelve thousand years ago. This automatically eliminates certain Loch Ness monster candidates, primarily the reptiles, amphibians and invertebrates.
Today, without the weight of ice, the land has risen and the surface of the loch would naturally stand at about 42 feet (12.8m) above sea level, but during the building of the Caledonian Canal, completed 1822, Telford built a weir at Loch Dochfour SATPIC 1 raising the level of the loch by 9 feet (3m) and saving the necessity for a lot more excavation to make that area navigable. The mean height of the surface of the loch above sea level is now taken as 51 feet (15.5m) although in recent years the wetter winters may have increased the mean somewhat.
When the ice retreated the area would have been an extremely barren landscape. It may be hard to imagine the lack of trees, or even grass, rainfall washing deposits off the hills into the loch. Gradually wind-blown seeds would have introduced vegetation, the first trees being the silver birch which is still here in huge numbers. As part of the Loch Ness Project's Rosetta Project an examination of the sediments has shown that silver birch pollen existed here just after the retreat of ice. Once you have a few grasses and trees the birds and animals would have begun to enter the new habitat. They would bring berries and heavier seeds thus continuing the movement of the Caledonian Forest northwards. Throughout this period the heavier wind-blown seeds like sycamore and ash would have been carried northwards until the Highlands mixed forest was established.
While the loch would gradually become populated with cold-water fish, the land saw a far greater variety of life including wolves, bears, beavers and elk ... all extinct here now, although the last wolf in the area was only shot in the nineteenth century. That wolf was known as Altsaigh SATPIC 22 and the name is still used for the burn (stream) which enters the loch from the northern side half way along its length. It was here that Altsaigh was killed.
Mankind entered the Great Glen following the animals. The Picts left their mark throughout the glen. Gradually they were superseded by the Scots who had come across from Scotia (Ireland) around the sixth century, although the "amalgamation" appears to have been relatively peaceful. Certainly there is no implication that the Scots conquered the Picts as they were outnumbered by around 20 to 1. Even today the Picts/Celts represent the major part of the Scottish population. At the beginning of the last millennium the Scots elected their kings and this was the time of Kenneth, Duncan and Macbeth. Interestingly it was a Scottish King, James VI who also became king of England when Elizabeth Tudor died and he unified the countries, conveniently handing Scotland to England on a plate when he moved his court south when becoming James I of England. Today many of us are looking for Scotland to become an independent nation within the European community and, in 1997, a measure of devolution occurred with the creation of the Scottish Parliament.
This brings us up to date, but I will be expanding upon this section in the future.