The Cuillin Round Ultra Run

The Cuillin Round is one of the most challenging and exhilarating mountain ultra-running challenges in the UK, set in the rugged landscape of the Isle of Skye in Scotland. This demanding route links multiple peaks around Glen Sligachan, known as the "Ultimate Rock & Run" 24-hour challenge. If you love scrambling/ easy climbing and ultra running, then this should certainly be on your "Ultra Running List"

The Cuillin Round: The Ultimate 24 Hour Rock & Run Ultra Running Challenge

If you're an ultra runner seeking the next adventure or challenge that's equivalent to that of many of the UK's 24-hour challenges, such as the "Big 3" (Bob Graham, Paddy Buckley and Ramsay's Round), then this is a must. The route links up 60 tops, including all 12 of Skye's Munro's. The Cuillin Round traverses The Black Cuillins, The Red Cuillins, Belig, Garbh-bheinn, Sgurr nan Each, Clach Glas Traverse, Blabheinn, Sgurr Hain and Sgurr na Stri. The route involves lots of technical scrambling terrain in some of the finest positions in the Scotland.

What is the Cuillin Round Ultra Run?

The Cuillin Round is one of the toughest and most thrilling mountain ultra-running challenges in the UK, set in the rugged landscape of the Isle of Skye in Scotland. This remarkable route, encircling the peaks around Glen Sligachan, is known as the "Ultimate Rock & Run" 24-hour challenge. From my own experience completing it, I can say that the effort required matches that of any other 24-hour ultra-running challenge in the UK, such as the Bob Graham Round, Ramsay's Round, or Paddy Buckley Round. While the Cuillin Ridge is famous for its technical difficulty and challenging navigation, this is only part of the Cuillin Round's demands. The route includes traversing the Red Cuillin, Garbh Bheinn, Clach Glas, Bla Bheinn, Sgurr na Stri, and many other peaks.

The Route: A Closer Look

The Cuillin Round is the ultimate 24-hour 'Rock and Run' challenge across the Isle of Skye's iconic Cuillin range, combining running and scrambling. Covering approximately 37 miles (60 kilometers) and over 7,500 meters of ascent, the route includes summiting 60 Cuillin tops, with a dozen Munros (Scottish mountains over 3,000 feet) and an equal number of Munro tops, including the notable Knight's Peak.

This challenge requires high endurance fitness, strong navigation skills, and scrambling experience. While no technical climbing gear is needed, participants face sustained, exposed scrambling that reaches difficulty levels similar to traditional climbing grades, around Diff (Difficult). Given the goal of completing the route in under 24 hours, this challenge is typically done as an un-roped scramble.

The Cuillin Round was first completed by Rob Woodall in 1999, who finished in 23 hours and 28 minutes. He advises that those needing roped assistance might struggle to finish within 24 hours and should consider a more leisurely pace. Yiannis Tridimas, the only other person known to have attempted this round, completed it in 21 hours and 21 minutes in 2000, adding an additional top to the route, making it 60 tops in total.

I completed the challenge in June 2023 in 19 hours and 39 minutes. Inspired by my completion, Finlay Wild set a new record in May 2024, finishing in just 13 hours and 4 minutes.

This round is inspired by the Trans-Cuillin route, which includes 70 tops. Although few have attempted the Cuillin Round, it remains a rare and prestigious achievement in the ultra-running and mountain scrambling community. I set a new record less than two weeks before attempting the Cuillin Round, as I was in peak fitness, fully recovered, and had ideal weather conditions. Read more about my experience on this blog.

The Terrain of The Cuillin Round

The Black Cuillins

The Black Cuillin Ridge, located on the Isle of Skye, is one of the UK's most iconic and challenging mountain ranges. Stretching approximately 12 kilometers (about 7.5 miles), the ridge features 11 Munros and 12 Munro tops, including the Knights Peak. Made primarily of gabbro rock, the ridge is known for its grip and rough texture, ideal for scrambling. However, its exposure and technical sections demand high mountaineering skills. Completing the full traverse of the Black Cuillin Ridge is a significant undertaking, requiring not only physical fitness but also rock climbing and navigation skills, making it the ultimate ultra-running challenge for those who love combining climbing and scrambling with endurance running.

For ultra-runners, the Black Cuillin Ridge represents the peak of technical mountain running challenges, especially when additional sections like the Red Cuillins, Clach Glas traverse, and Sgurr na Stri are included. Unlike traditional ultra-marathons focused on distance and endurance, the Black Cuillin Ridge and Cuillin Round involve extensive scrambling and climbing, often up to Moderate or Difficult climbing grades. Runners must navigate narrow ridges, vertical drops, and steep ascents and descents while managing the physical demands of a long-distance run. The terrain requires constant vigilance, as loose rocks and the ridge's exposed nature pose significant risks. Running the Black Cuillin Ridge is not just about speed but about moving efficiently and safely through complex and often dangerous mountain terrain.

Successfully running the Black Cuillin Ridge demands a unique blend of endurance, agility, and technical climbing ability. Skye's weather can change rapidly, adding difficulty with rain, wind, and mist, turning the ridge into a hazardous environment. Ultra-runners must be well-prepared for these conditions, as they test physical stamina, mental resilience, and decision-making under pressure. Completing the Cuillin Round in one push is a rare achievement, showcasing an athlete's ability to conquer one of the UK's most formidable mountain challenges.

The Red Cuillins

The Red Cuillin contrasts sharply with the Black Cuillin, featuring gentler, rounded hills made primarily of granite. While less technically challenging, this section is physically demanding, with long, steep ascents and descents over grassy, often boggy terrain. A notable climb is Glamaig, which rises over 800 meters from sea level, offering continuous steep slopes and a real test of mental toughness. However, its 360-degree summit views are among Scotland's finest.

The Red Cuillin allows for faster movement compared to the Black Cuillin, but the risk of navigation errors increases due to less defined paths. This part of the round provides a chance to recover slightly before tackling more strenuous sections.

Garbh Bheinn, Clach Glas Traverse, and Blàbheinn

The Garbh Bheinn, Clach Glas, and Blàbheinn (Blaven) traverse is a challenging and scenic route on the Isle of Skye, offering a captivating experience for ultra-runners. Starting with Garbh Bheinn, a rugged and less-travelled peak, runners are treated to stunning views of the surrounding landscapes, including the Cuillin range. Garbh Bheinn's rocky slopes and steep inclines test stamina and technical abilities right from the start.

Next, runners move to Clach Glas, known as the "Skye's Matterhorn" for its sharp, pointed shape and steep rock faces. Clach Glas offers a series of scrambles that require careful navigation and a good head for heights. The technical challenges increase as runners traverse its knife-edge ridges, where solid footing and strong scrambling skills are essential. The traverse between Clach Glas and Blàbheinn includes exposed sections demanding both physical and mental agility, making this segment a highlight for those seeking a true mountain adventure.

The final ascent to Blàbheinn offers breathtaking panoramic views that extend to the entire Cuillin Ridge and beyond, providing a rewarding climax to the run. Blàbheinn requires more scrambling and steep climbing, but reaching its summit offers a sense of accomplishment and the chance to take in Skye's rugged beauty. Completing the Garbh Bheinn, Clach Glas, and Blàbheinn traverse as an ultra-run requires endurance, speed, and the ability to handle exposed, technical terrain confidently. This route offers intense physical challenges and Skye's unparalleled mountain beauty, making it a prized route for seasoned ultra-runners and mountain enthusiasts.

Sgùrr Hain & Sgùrr na Stri

Sgùrr Hain and Sgùrr na Stri provide a unique ultra-running experience on the Isle of Skye, combining rugged terrain with some of Scotland's most breathtaking views. Sgùrr Hain, though not the tallest peak, offers a challenging ascent with rocky paths and steep inclines, making it an excellent warm-up for the more demanding parts of the run. The route to Sgùrr Hain winds through dramatic landscapes, featuring sharp rocks and heather-covered slopes, showcasing Skye's wild beauty. Despite its lower elevation, the summit offers panoramic views of the Cuillin range and Loch Coruisk, making the effort worthwhile.

Continuing to Sgùrr na Stri, runners encounter one of Scotland's most spectacular viewpoints. Known for its iconic vistas, Sgùrr na Stri offers unparalleled views over Loch Coruisk and the jagged Cuillin peaks. The ascent involves steep climbs and scrambling, requiring good navigation skills and a head for heights. The terrain is rough and uneven, demanding both physical endurance and careful footwork. Reaching the summit of Sgùrr na Stri is a pinnacle moment, with sweeping views that extend across the island and towards the mainland. This mix of challenging, technical running and the chance to experience one of the UK's most beautiful landscapes makes the Sgùrr Hain and Sgùrr na Stri ultra-run an unforgettable adventure.

"I completed the Cuillin Round on June 1, 2023, starting at the bottom of the Bla Bheinn Ridge and going clockwise (beginning with Sgùrr Hain and Sgùrr na Stri, followed by the Cuillin Ridge). I chose this route for several reasons: I could sleep in my car at the Kilmarie car park (about 4 km away) and easily walk to the ridge base to start. Starting with the smaller hills before tackling the Cuillin Ridge's technical difficulties allowed me to follow the usual route direction. Most of the peaks are easy to navigate, and finishing on Clach Glas in the dark required fewer technically demanding decisions when tired. The terrain and scenery are some of the best in the UK, but only if you get the right weather!"

Navigation and Technical Skills Required

Navigating the Cuillin Ridge is notoriously difficult, even for seasoned mountaineers. The ridgeline is complex and convoluted, with numerous spurs and ridges that can easily lead to disorientation, especially in poor visibility. Many sections of the ridge require scrambling (a mix between hiking and rock climbing), and some require full climbing equipment, including ropes, harnesses, and protection, although the Round is traditionally completed un-roped. The ridge's narrow paths and exposure to steep drops mean that a head for heights and confidence in moving over technical terrain are essential.

The challenge's severity is further heightened by the ridge's isolation and the limited escape routes. Unlike many mountain ranges, where retreat to lower ground is straightforward, the Cuillin Ridge often requires committing to long sections before any viable descent option is available. This means that once on the ridge, you're committed to completing or reversing sections to find a safe exit.

For those attempting the Cuillin Round, thorough preparation is key. This includes familiarizing oneself with the route, understanding the necessary climbing and scrambling techniques, and being prepared for all weather conditions. Even in summer, the weather in the Cuillin can change rapidly, with rain, wind, and fog being common. These conditions can make an already challenging route even more dangerous, turning solid rock into a slippery surface and obscuring visibility.

Completing the Cuillin Round within 24 hours is a significant achievement that requires not only physical fitness and endurance but also mental toughness, navigational skills, and the ability to move confidently over complex and exposed terrain. It remains a testament to the skill and determination of those who undertake it and a true classic in the world of mountain ultra-running.