While the General Wade road was finished in 1731, the pass was used before this by cattle drovers. Ironically the first actual army to use it was the opposition, Bonny Prince Charlie with his Jacobite army. Once the road was completed the pass was crossed more regularly. One regular user was the minister of Laggan who was courting a lady who lived in Fort Augustus. She did eventually consent to become Mrs Grant so his determination was well rewarded. Probably the most regular users of the road over the pass nowadays will be the engineers who service the line of electricity pylons that follow the route. Their vehicles are exempted from the order that prohibits motor vehicles. Driving over the pass on your Shogun or whatever became quite fashionable, and considerable damage was done. Because of this motor vehicles are now prohibited.
It's worth remembering of course that at the time the Wade road was built, traffic over it would be on foot, wheeled vehicles in the highlands being a rarity. One person said: The whole road is rough dangerous and dreadful, even for a horse. The steep and black mountains and the roaring torrents rendered every step the horse took frightful, and when he attained the summit of the zig-zags up Corrieyairack he thought that the horse, man and all would be carried away, so strong was the blast. Soldiers occasionally died on the pass from over-fortifying themselves with whisky, make sure it doesn't happen to you!
Route Description
The off-road section of the Corrieyairack Pass runs from just south of Fort Augustus to Melgarve west of Laggan in Speyside. BaseCamp MTB at Laggan Wolftrax offer a shuttle service for those riding the Pass. It climbs from 60 metres at the Fort Augustus end, to 775 metres at its highest point. This military road is one of General Wade's, it was finished in 1731. There are two notices at the start at the Fort Augustus end. One tells you that the road over the pass is now an ancient monument and is in the care of the Secretary of State for Scotland (Historic Scotland), it is an offence to damage it. Another notice, by Highland Council, says that motor vehicles are prohibited; bikes are allowed. Travelling west to east is best for mountain biking as the descent on the east side is more rideable.
Fort Augustus Approach
The General Wade road now starts near the south end of Loch Ness, from a minor road connecting the A82 to the B862. At the south (A82) end the minor road is signed Ardachy, there is no sign where the minor road joins the B862. The first section of the Wade road is badly eroded, there is a gate to stop vehicles, but I doubt that any vehicle could get up it easily. After that the going gets better. The road climbs south-west at first, to get round the Culachy Burn, passing a fine series of waterfalls. After this it turns south-east and begins the first of the many zig-zags it uses to reach the summit of the pass. The climb is extremely steep, and the surface is quite rocky. Inevitably you will have to walk some of it. There are brilliant views of the Great Glen and Loch Ness as you climb higher and higher. Glen Tarff is quite pretty, with remnant pine woods near the river. Eventually you climb completely clear of the glen and the scenery is more forbidding. Finally you reach the summit at 775 metres. You might think that the worst is over, for all the rest is downhill. Don't be deceived; the descent is very steep and rocky, with sharp zig-zags in the steepest sections, extreme care is necessary.
Garva Bridge Approach
You get to Garva Bridge by taking a minor road from Laggan. This is a pleasant bike ride in itself. As you approach the Wade road is clearly visible, climbing steeply up the hill. One of the Wade bridges is just north of the current bridge here and is worth a short walk to look at. The first section is completely straight, after that the track begins a series of eleven zig-zags to get to the top. The fact that the course of these zig-zags is still in place indicates just how well the road was surveyed in 1730. Look back and you can see right over Speyside to the Cairngorms with the River Spey far below. Again the descent on the other side needs extreme care.