The tarmac ends, and in a sense so does the modern Highlands. Glen Affric is reached by a single-track road that climbs west from Cannich, through Strathglass, and gives up a few kilometres past the lochs, and that dead end is exactly why the glen has stayed so intact. People who know Scotland well tend to name it as the finest glen in the country, and it is hard to argue once you are in the middle of it, among old pine trees with Loch Affric and its islands lying in front of you.
What you are looking at is a remnant of the Caledonian forest, the Scots pine woodland that once covered much of the Highlands before felling, grazing and burning pushed it back into a few strongholds. Some of the trees here are centuries old, wide and twisted, with orange bark that glows when the sun is low. Birch, rowan and juniper fill the gaps. Red deer move through the hillsides, golden eagles hunt the ridges, and the shy residents, red squirrels, pine martens and capercaillie, are the ones most visitors never see. Conservation groups have spent decades fencing, planting and letting the forest regenerate, and you can see the young trees coming up.
On a bike, the road is slow by necessity. It is narrow, with passing places that you actually need to use, plenty of blind rises and the occasional cyclist, walker or sheep. The surface is generally good but patched, and in places the pines shade it so it stays damp long after the rest of the glen has dried. That suits the pace. Take it gently, stop at the car parks, switch off the engine and listen; in the middle of the day the loudest sound is often the wind in the needles. Autumn, with golden birches and bracken the colour of rust, is when the glen is at its best, and it is also when the midges finally relent.
The nearest proper services are back toward Drumnadrochit or on the road to Inverness. The dams and hydro works in the upper glen are a reminder that this wilderness has been engineered more than it looks, but the effect is mild, and the landscape wins.