The Carn Mor Dearg Arete: Are We Walking Responsibly?

The Carn Mor Dearg (CMD) Arete is rightly considered one of the finest mountain days in the UK. A sweeping, atmospheric ridge walk that provides the most dramatic introduction to the north face of Ben Nevis, it is a rite of passage for every serious hillwalker. But as we enjoy this classic route, we have to ask ourselves: how are our feet affecting the very landscape we come to admire?

Specifically, we need to talk about the ascent of Carn Mor Dearg from the Allt a' Mhuilinn path.

If you have walked this route recently, you have almost certainly witnessed the degradation. !00m beyond the prominent birch tree on the path, you leave the path to start the climb. There is a prominent, heavily eroded strip of ground tearing through the peat bog. It is an eyesore, yes, but it is also an ecological scar.

​The Myth of Individual Impact

It is easy to justify walking through the bog. You tell yourself, "I am just one person, my footprint won't make a difference." And, in isolation, you are right. Your individual impact is negligible.

However, the Scottish Outdoor Access Code (SOAC) operates on the principle of collective responsibility. When hundreds, or even thousands, of us follow the exact same line over soft ground, the cumulative impact is massive. We are not just compressing soil; we are accelerating erosion, destroying fragile upland vegetation, and exposing the underlying peat.

When peat is exposed from underneath its vegetation cover, it dries out, oxidises, and releases stored carbon dioxide back into the atmosphere when it gets washed away by the rain. What starts as a narrow trod through the grass and heather becomes a wide swath of erosion and a significant environmental contributor to carbon emissions and habitat loss.

The boggy path leaving the Allt a' Mhuilinn path.

Are We Breaking the Code?

The Scottish Outdoor Access Code promotes the right to roam, but it is predicated on responsible behaviour. A key pillar of the Code is to "respect and care for your environment."

If we choose the path of least resistance when a more sustainable alternative is available, we are failing to uphold that specific pillar of the Code. We aren't breaking the law, but we are arguably failing to act as responsible custodians of the landscape. When a viable, less damaging alternative exists, "access" ceases to be the issue; "responsibility" becomes the defining factor.

Leave the Allt a' Mhuilinn path about 500m beyond the prominent birch tree on the path.

A Better Way Forward

There is good news. You don't have to contribute to the erosion of that bog.

There is a better, more sustainable route that follows a terminal moraine four hundred metres further up the Allt a’ Mhuilinn path (500m beyond the prominent birch tree). It is not only kinder to the mountain, but it also offers a far more enjoyable ascent, avoiding the worst of the deep, sloppy peat and keeping your boots significantly cleaner.

At Abacus Mountain Guides, we believe that expert judgment isn't just about managing risk on steep ground; it is about managing our footprint on the hill. We have mapped a route that utilises this terminal moraine, bypassing the bog entirely.

If you are planning to head up the CMD Arete, I encourage you to seek out this alternative line. We have the GPX file to download, and we are more than happy to share the route knowledge to ensure your day out is as sustainable as it is spectacular.

Let's enjoy these mountains in a way that ensures they remain just as dramatic for the walkers who follow us.