An Teallach is classed as a Munro and a Marilyn and lies to the southwest of Dundonnell. This fabulous mountain is perhaps the most imposing in United Kingdom, and offers a full and challenging day out for those who wish to explore its ten distinct summits. The highest of these is Bidean a’Ghlas Thuill, which rises in height to 1,062 m (3,484 feet), with Sgurr Fiona being the second highest and also a Munro at 1,060 m (3,478 ft).
Overall, the lower reaches of An Teallach are boggy, then ascend into challenging scrambling territory, although the worst of this can be avoided by following the bypass paths or visiting only the main peaks. The simplest route of ascent begins in nearby Dundonnell.