The only way is up for 100km: Taking on the longest climb in the world

We weren’t even halfway up the mountain and it was getting difficult. Having climbed 60km of the Cordillera Central since dawn, by midday I was writhing on the bike on the last curves before reaching Murillo, a traditional Andean village with colourful facades. The village sits 3,000m above sea level on the slopes of the Nevado del Ruiz volcano, and from here, on the clearest mornings, you can see the permanent layer of frost on the volcano’s upper slopes, and the occasional plume of smoke, but today we weren’t so lucky. Most of the next four hours would be spent under drizzle and fog – all the way to the summit.

Ascending the Alto del Sifón, the longest paved climb in the world, begins at 350m above sea level, in the Magdalena River valley. The road leading to the summit is well-surfaced and initially passes through the ruins of Armero, a prosperous town that was devastated by the last eruption of Nevado del Ruiz in 1985. From there, at least eight hours of pedalling lead to the top of the Cordillera Central, one of the three branches of the Colombian Andes. But the goal cannot be seen from the start, from where a cool breeze blows from above as the first rays of the sun break through.

Since the first Vuelta a Colombia bicycle race was run in 1951, amateur and professional cyclists have climbed these slopes via the only available route: an 80km climb with a cumulative elevation gain of 3,200m at an average gradient of 4%. This climb runs from the nearby town of Mariquita to Alto de Letras, located at 3,700m altitude, on the mountainous border dividing two coffee-producing regions: Tolima and Caldas. For years, Letras was known as the longest bike climb in the world. But today, thousands of Colombian and visiting cyclists want to try another route, on the newly-paved road that has become the highest in this rugged country: just over 100km now connect the Magdalena Valley with Alto del Sifón, located at 4,150m high on the slopes of the volcano. With an average gradient of 4.5%, the most ambitious cyclists must overcome 4,500m of elevation gain on their way to conquering the colossus.

Seduced by the prospect of this adventure, I prepared for several months with long rides around Bogotá, the capital where I live, located at 2,600m above sea level. I am not a professional cyclist but just a writer who for the last 10 years has been captivated by cycling, a national passion that drives thousands of Colombians into the mountains. My training included gruelling routes with long continuous climbs of 30–40km. Still, it was impossible to rehearse for a 100km climb.

Caffeinated climbing

On the lower slopes, tall trees give way to symmetrically planted coffee bushes, our traditional crop whose plants cling to the slopes like tenacious cyclists. This area used to be a war zone: nearby is the birthplace of the Revolutionary Armed Forces of Colombia (FARC), the largest and oldest guerrilla group in the West, now demobilised. Today the area exudes safety and peace. Until October 2023, the road was a dirt and gravel path. Now, the paved road winds through sharp curves as it gains altitude, and the light traffic allows us to ride without fear.

Cyclists have become key customers for the local communities, and on weekends vehicles circulate selling assistance services; motorcyclists offer drinks, minor repairs, or a little air for the tyres. Occasionally small shops appear at the side of the road, providing a chance to stop and refuel. The classic snack among Colombian cyclists is the bocadillo, a sweet made of guava and sugar – perfect fuelling for the longest climbs.

The paving of the road from Murillo to the volcano has given this new route a huge boost. Today, hundreds of Colombian and foreign cyclists include this climb among their main goals each year, and tourism is growing rapidly. A climb of this magnitude must be done at a moderate pace, keeping plenty in reserve. Riders not accustomed to it also need to adapt to the altitude. Riding a 36–30 set-up, I focus on maintaining a comfortable pedal stroke, never straying above my comfort zone. I rise out of the saddle frequently, altering my position to avoid aches.

In the middle of the climb, between 1,500 and 2,000m, on a tropical plateau located between the valley and the snow-capped peaks, I notice farmers, protected from the sun by broad-brimmed hats, picking coffee by hand, alleviating the monotony by playing songs on their phones – the music drifts to the roadside, along with fragrant scents: soursop, passion fruit, orange, and tangerine.

At around 11am, I arrive in Líbano, the first major town on the route. It has 45,000 inhabitants and is an ancient indigenous village that was colonised in the mid-19th century by farmers from the western side of the mountain range, where the three regions of the so-called coffee axis converge: Caldas, Risaralda and Quindío. After hours of tranquillity, the bustle of the town, with its restaurants, hotels, bakeries and cafes, feels almost like sensory overload. We’re 35km in – around a third of the total distance – so it’s the perfect place to stop for a late breakfast or early lunch. If you decide to divide the climb into two stages, it’s also a good place to stay the night. For me, the stop is a chance to prepare, unhurriedly, for the most demanding segment of the adventure.

The next 23km take me skywards to Murillo, the highest municipality in the entire department of Tolima, located 3,000m above sea level. During this stretch, the gradients become more difficult as we approach the páramo, an alpine ecosystem that exists only in the tropics. The surroundings gradually become more and more rural, solitary and quiet; we pass between gorges that allow me to see how far I have climbed. Far below, the Magdalena River shimmers and flows through the wide valley between two mountain ranges, the Central and the Oriental.

At midday, on a false flat preceding the highest segment of the route, we encounter two cyclists going back and forth, repeating sprints on the only level kilometre of the entire route. On either side, the road is lined with green meadows and trees, and a few red-roofed farmhouses. The highest peaks, shrouded by thick cloud, appear for the first time above the forests in the middle distance.

A succession of hairpin bends between waterfalls and trees turn the route into a green tunnel, and lead me, finally, toward Murillo. But for the first time, my head begins to betray me: my legs are hurting and so is my back. Exhaustion is setting in from the hours of constant climbing that has allowed only a few breaks on sporadic descents. The route suddenly begins to seem monotonous, and I decide to distract myself from the discomfort and hunger with some music through my headphones.

There are still 7km to go to Murillo, and another 34km to the summit, but the music works its magic, lifting my mood. The shade of the trees shelters me as the sun reaches its highest point, and before I know it I’m entering the town. From here you can see the imposing Nevado del Ruiz volcano.

Last chance saloon

Murillo is the last place where you can stop to eat and buy supplies before facing the final kilometres of climb. It’s a small town of only 5,000 inhabitants, with multicoloured wooden houses. It was once a sleepy peasant village, but the new road has brought tourists, as well as groups of cyclists. Shops now offer electrolyte drinks and snacks, while cafes and restaurants have sprung up, with plentiful tables at the central plaza. I stop for two beers and a large plate of Creole food, traditional workers’ fare: rice, pork, beans, plantains, and a fried egg. The result is a resurrection in my energy levels.

From Murillo, I only have about 1,500m of ascent left to complete, and the route is no longer constant climb but undulating. Still, there are 25km left to cover, and the volcano is intimidating. Looking up at it, I ask myself one last time: do I really want to do this? The answer is yes, absolutely.

Over the years, I’ve discovered I have great endurance: after 150–200km, I start to feel good and enter an almost Zen-like state, where everything becomes secondary to the mechanical act of pedalling. Voice messages and photos on WhatsApp from my son and my wife provide extra motivation, but my greatest drive is the need to accomplish, to reach the top.

Over this final section, the vegetation transforms, and on the humid slopes, only grass and frailejones thrive – a towering plant that gathers battalions of upright stems at high altitudes. The landscape heading to Alto del Sifón, with the last 20km above 3,500m, becomes increasingly inhospitable, imposing and overwhelming. The air is perceptibly thin, and the heart and lungs demand a moderate pace; heroic bursts of effort are ruled out.

My body is now on a kind of autopilot, moving like a sleepwalker, guided by instinct and habit. By 6pm the sun has disappeared and it’s getting cold. The weather in the páramo changes rapidly, clouds move swiftly, drizzle is frequent, and the temperature hovers around 2–3ºC.

The volcano and surrounding mountains exert their presence with a mysterious force. Even the most sceptical among us might feel the presence of something higher: an energy that evokes reverence. Between the final curves, in complete silence, accompanied only by the faint sound of my tyres on the wet road, I stumble upon the Lagunillas River, the same one that carried tons of water and mud in the 1985 eruption, devastating the town of Armero and killing more than 20,000 people.

Despite the cold, pedalling – and several layers of kit – keeps my core warm. Shortly before reaching the summit, a brief window of opportunity opens: the rain and mist clears, allowing me to stop and appreciate the beauty surrounding me. Two cars of bundled-up tourists pass by and honk their horns to toast my achievement. I raise an arm in gratitude, and soon I am alone again in the immensity of the mountain range.

The mist swirls around me, permitting brief glimpses of scenery. My journey’s start at the base of the climb is no longer visible, only remembered as in a distant dream. I want to remember it all: the immensity of the valley far below, the slow curve of the Magdalena River, the climb uncoiling beneath me like a great serpent. This ride imprints itself for life, open to anyone with the nerve to attempt it and the legs to endure it.

The final kilometres have moved me deeply – the silence, the biting cold, the vulnerability of exhaustion. At the summit I find myself overwhelmed, elated, and unexpectedly in tears. It is hard to find words for this feeling, but Giancarlo Brocci, the founder of L’Eroica, has a phrase for it: la bellezza della fatica – the beauty of fatigue.

Alto del Sifón in numbers

Location: Murillo, Tolima, Colombia
Distance: 105km
Height: 4,149m
Average gradient: 4.5%
Max gradient: 12%
Total riding time: 9hr

How to get there: Fly from London to Bogotá (typically £700–900 return). Onward travel, by car or bus, to the base of the climb near Armero takes a full day. Avoid travelling in Colombia’s rainiest periods (April–May and Oct–Nov).

This feature was originally published in the 15 January 2026 print edition of Cycling Weekly magazine – available to buy on the newsstand every Thursday (UK only) while digital versions are available on Apple News and Readly. Subscriptions through Magazine's Direct.