The Zoncolan from Ovaro is 6.3 miles (10.1 km) at an average 11.9%: 3,947 ft (1,203 m) of climbing, from 1,722 ft (525 m) to 5,676 ft (1,730 m). Those are the Giro d’Italia’s figures, and they match Wikipedia (10.1 km and 1,210 m), salite.ch (10.5 km and 1,210 m) and CyclingCols (9.9 km and 1,204 m).
The climb, section by section
- First 1.2 miles, 2 km (about 7%). Out of Ovaro. It’s the only “normal” section.
- Km 2 to 7, miles 1.2 to 4.3 (over 15%). Three miles (5 km) never below 15%, with 20-22% ramps. CyclingCols gives 15.4% for its steepest 5 km and 17.2% for the hardest kilometer.
- Last 1.9 miles, 3 km (about 9.5%). More manageable, with three short tunnels near the top.
The middle section is confirmed by the Giro and CyclingCols; the first and last are what’s left of the total, so treat them as approximate. The summit is between 5,676 and 5,741 ft (1,730 and 1,750 m) depending on the source.
Giro d’Italia history
The Giro first came here in 2003, up the Sutrio side, and Gilberto Simoni won (Pantani was fifth). The Ovaro side debuted in 2007, with another Simoni win. Since then the winners have been Ivan Basso (2010), Igor Antón (2011), Michael Rogers (2014) and Chris Froome (2018, a few seconds ahead of Simon Yates), all from Ovaro, and Lorenzo Fortunato (2021), from Sutrio. In the Giro d’Italia Women, Fabiana Luperini (1997) and Annemiek van Vleuten (2018) won.
The pros run recreational-rider gearing here: in 2018, Froome, Bennett and Pinot used 34x32, and Yates, Chaves and Dumoulin 34x30.
When to go, water and traffic
There’s very little traffic. The tunnels near the top may be dark: bring a light. Many riders recommend descending via Sutrio, because the Ovaro side has gravelly patches. Other sides: Sutrio (8.4 miles, or 13.5 km, at about 9%, with a steep final 2.2 miles, or 3.5 km) and Priola (5.5 miles, or 8.9 km, at 12.8%).
What gearing to use
If the pros use a 34x32, you need a 34x34 at minimum, and ideally a 32x36 or lower. At 3 W/kg (watts per kilo of body weight) and 159 lb (72 kg), you’ll be doing about 3.7 mph (6 km/h) on 15%; on a 34x34 you’ll pedal around 50 rpm, dropping to 37 rpm on the 20% ramps. Run the numbers in the gear calculator.
Tips
- The first 1.2 miles (2 km) are your warm-up: ride well below your pace.
- In the middle section, stay seated with the highest cadence you can manage.
- Descend via Sutrio, with your brakes in perfect shape.
Frequently asked questions
How long does it take to climb the Zoncolan from Ovaro?
A 159 lb (72 kg) rider on a 21 lb (9.5 kg) bike takes about 1 h 19 min at 3 W/kg (216 W), 1 h 35 min at 2.5 W/kg and 1 h 00 min at 4 W/kg. Work out your own time with your weight and power in the calculator on this page.
What gearing do the pros use on the Zoncolan?
At the 2018 Giro d'Italia, Froome, Bennett and Pinot ran 34x32, and Yates, Chaves and Dumoulin 34x30.
Who has won on the Zoncolan?
Gilberto Simoni (2003 and 2007), Ivan Basso (2010), Igor Antón (2011), Michael Rogers (2014), Chris Froome (2018) and Lorenzo Fortunato (2021).
Does the Zoncolan have tunnels?
Yes, three short tunnels near the top. Bring a light in case they aren't lit.