Alto El Sifón is 54.6 miles (87.9 km) of climbing and 13,173 ft (4,015 m) of elevation gain from Armero (Tolima), at about 1,150 ft (350 m) above the Magdalena valley, to the 13,530 ft (4,124 m) summit on the slopes of Nevado del Ruiz. The average is 4.6%, but what is frightening is the total: it is one of the few paved climbs in the world with more than 13,100 ft (4,000 m) of gain. Climbfinder ranks it among the five biggest climbs in the world by elevation gain.
What the climb is like
- Armero to Líbano. You start among the memorials to the 1985 Armero tragedy, when a mudflow from Nevado del Ruiz buried the town. The first 19.9 miles (32 km), to Líbano, add up to nearly 4,900 ft (1,500 m) of climbing through coffee farms.
- Líbano to Murillo. The road keeps climbing at a moderate grade. By the time you reach Murillo you have about 9,800 ft (3,000 m) of climbing in your legs.
- Murillo to the top. The landscape turns to páramo: frailejón plants, a lake near the summit and views of Nevado del Ruiz. The grade is gentle (the steepest 100 m reach 8.8% according to Climbfinder), but you are above 11,500 ft (3,500 m).
The sources do not measure exactly the same thing: Climbfinder gives 54.6 miles (87.9 km), 13,173 ft (4,015 m) of gain and a summit at 13,530 ft (4,124 m); PJAMM starts at a different point in Armero and gives 49.8 miles (80.2 km), 13,064 ft (3,982 m) of gain, 4.6% and a summit at 13,281 ft (4,048 m). We use Climbfinder’s, which is the most complete.
When to go, weather, water and traffic
You can ride it all year, but the rainy seasons (April-May and October-November) bring more fog and a higher risk of landslides. You start in tropical heat and finish on the páramo above 13,100 ft (4,000 m), where it is properly cold and the air holds about 40% less oxygen than at sea level. Bring a jacket, gloves and warm layers for the descent, and check activity alerts for Nevado del Ruiz, an active volcano.
The pavement is in very good shape almost the whole way and traffic is light. There have been occasional road closures because of protests on the lower part: check conditions before you go. There are stores in Líbano and Murillo; above that, almost nothing.
What gearing to use
The grade does not call for extreme gearing, but the altitude and the hours do. A 34x30 or 34x32 lets you keep spinning when you run short of watts above 11,500 ft (3,500 m). Compare options in the gear calculator.
Tips
- It is a five- to six-hour day: plan your food as you would for a long mountain stage.
- Sleep in Murillo and ride the upper part the next day if you are not acclimatized.
- If you are coming from sea level, try Alto de Letras first, its slightly easier neighbor.
Frequently asked questions
How long does it take to climb Alto El Sifón?
A 159 lb (72 kg) rider on a 21 lb (9.5 kg) bike takes about 5 hr 09 min at 3 W/kg (216 W), 6 hr 02 min at 2.5 W/kg and 4 hr 05 min at 4 W/kg, not counting stops. Work out your own time with your weight and power in the calculator on this page.
Is Alto El Sifón harder than Alto de Letras?
Yes: it has about 1,440 ft (440 m) more climbing (13,173 ft / 4,015 m versus 11,729 ft / 3,575 m), it is 5 miles (8 km) longer and it finishes almost 1,480 ft (450 m) higher, above 13,450 ft (4,100 m). PJAMM ranks it as the hardest climb in Colombia, ahead of Letras.
Is there water and food on the way up El Sifón?
Yes, in Líbano, around km 32, and in Murillo, after about 9,800 ft (3,000 m) of climbing. Above Murillo there are hardly any services: carry food and warm clothes.