The route of the Heartbeat Challenge certainly lives up to its name. Your heart will be pumping from the off, with a steep uphill just round the corner, though the real challenge comes later.
I opted to go for walking boots rather than running shoes when I headed out to Clava to test the course.
Beinn Bhuidhe Mhor - the highest point on the circuit - is a hill that's often bypassed without much thought. To those used to some of the more rugged terrain of the Highlands, it's a barren round lump unworthy of much comment.
However, those that have climbed the 548m hill know otherwise.
Starting out on the minor road near the Clava Cairns, the Heartbeat Challenge takes walkers and runners under the viaduct and up the very steep climb to a T-junction at Dalroy. Going right here, a left turn onto a wide vehicle track immediately before a bridge takes you onto the off-road part of the route.
While the track is steep in places, it does ease off to a more pleasant gradient in sections - albeit small sections - as it passes Finglack, where you veer right away from the buildings before following the track left, through a gate and into the forest.
I met a couple of runners and a few walkers on my trip, as well as a couple of estate workers, but it was peaceful up here and I'd recommend the walk up Beinn Bhuidhe Mhor any time.
As you emerge from the trees, you go through a gate, under the pylons and out onto the open hillside, still following an easy track. It levels here for a while before climbing gently again. Looking back you start to realise why this is such a fantastic place to come.
Already I could see the Beauly and Moray firths and the Kessock Bridge far below, and the views only got better, despite the uninspiring weather. On a clear day, you really can see for miles from the top, even out to Suilven in Sutherland.
At a junction, the route goes left to pass under the crags of Saddle Hill and then turns right - and you can see the next climb ahead. This track leads steeply to the summit of Beinn Bhuidhe Bheag, whose top is marked by a fairly large cairn, before continuing down to meet another track. The views along here are superb, as you look over Inverness towards the west.
The challenge route turns sharp left onto this track, which heads up Beinn Bhuidhe Mhor on a dug-out surface. If you get chance on the day, it's worth heading right through the peat at a tiny cairn to reach the trig point and - weather permitting - take in the fine panoramic views.
The track continues for a few more miles until it comes to a sudden stop.
This is where the challenge comes in. Hopping over the fence, you go right to follow it round a small crag towards a forest, then go left down the edge of a long, straight fence.
Here you're at the edge of a huge grouse moor on the Moy Estate - so best to avoid it after the glorious 12th, the date in August when the grouse-shooting season starts.
It's a boggy, soggy, rough, pathless route which eventually ends when you hit the railway line. Keep beside the fence to the very bottom, where a short track goes left to ford a burn and climb into the rough heather.
To be honest, I can't say for sure how the route makes its way through the heather and hags from here but I managed to follow a vague line parallel to the railway until I picked up a track of crushed heather which led to an industrial peat digging area.
A good vehicle track leads through the works then, after crossing Dalriach Burn, goes straight ahead through a gate with the forest on your right and a clearing to your left.
You soon reach a junction beside the Moy burn, where you go right to follow the estate track all the way to the Mains of Moy and the changeover to the bike.
It's only 10 miles on the bike - but there are some hills to tackle on this stretch too. Initially at least, it's fairly easy as you head for the B9154 and turn right onto it. This is part of the National Cycle Network (NCN) Route 7, and you follow the cycle sign right towards Inverness at the bottom of a downhill near Craggie.
This fine minor road is a superb cycle route - though the legs are no doubt suffering from the walk or run by now.
The Heartbeat route sneakily leaves the NCN by turning left just before it crosses the railway, instead heading steeply downhill to cross the River Nairn before climbing just as steeply up the other side. This is a tough one at this stage but that's the climbing finally over.
You just head right onto the B851 and follow it along to a crossroads, where you turn right down the speedy descent to Clava.
