Tunel Iscaycruz: Driving through one of the highest tunnels in the world
Tunel Iscaycruz is an extreme high-altitude mountain passage at an elevation of 4,905 meters (16,092 ft) above sea level, located in the Oyón province of the Lima region in Peru. Set deep within the high cordillera of central Peru, this 229.86-meter-long tunnel is a critical logistical asset for the Los Quenuales lead and zinc mines. Due to its staggering altitude, it surpasses the Punta Olímpica Tunnel, making it potentially the highest in South America and certainly one of the highest vehicular tunnels in the world.
| Road facts: Tunel Iscaycruz | |
|---|---|
| Location | Oyón, Lima Region, Peru |
| Elevation | 4,905m (16,092ft) |
| Length | 229.86 m (754.13 ft) |
| Surface | Totally unpaved / Gravel |
How difficult is the road to Tunel Iscaycruz?
The journey to the tunnel is a brutal technical challenge starting from the high-altitude Abra Rapaz. The 3-kilometer access road is a primitive, unpaved track that winds through the steep slopes of the Andes. The road condition is dangerous, defined by countless sharp curves and extremely narrow sections where passing oncoming mining furgonetas or heavy trucks is a high-risk maneuver. The logistics of the climb are dominated by the altitude; at 4,905 meters, the notorious lack of oxygen significantly reduces engine torque, forcing you to maintain high revs just to clear the steep, rocky ramps that lead to the tunnel entrance.
What are the main hazards on the Oyón mining route?
The primary hazard is the combination of the raw, unpaved surface and the sheer drops of the central cordillera. The road to the tunnel has no safety barriers, and the ground is often composed of loose gravel and shale that shifts under the weight of a vehicle. During the rainy season, the track can become a slippery mud trap, making traction nearly impossible even with a 4x4. Another physical reality is the constant traffic of heavy industrial vehicles related to the lead and zinc mining operations. These trucks have the right of way, and finding a safe spot to pull over on the narrow ledge sections requires technical precision and steady nerves.
Is the Tunel Iscaycruz accessible to the public?
While the tunnel serves the Los Quenuales mining operations, the route remains one of the most secluded and high-altitude drives in Peru. The weather at nearly 5,000 meters is unpredictable and violent; sudden snowstorms or heavy mist can reduce visibility inside and outside the tunnel to zero in minutes. There is no lighting inside the 229-meter passage, and the interior is often damp with groundwater seepage. Because of its extreme elevation, the road can be closed anytime due to snow accumulation or landslides, and there are no service stations or medical facilities within a reasonable distance.
What mechanical prep is needed for the 4,905m Peruvian crossing?
Before heading out from Abra Rapaz, verify that your 4WD system, low-range gears, and braking system are in perfect order. The descent from the tunnel requires engine braking to avoid boiling your fluid on the steep, unpaved switchbacks. Check your air filters; the fine mining dust and the high-altitude air require a clean intake to prevent the motor from suffocating. Ensure your tires have reinforced sidewalls to handle the sharp Andean rocks. Carry extra fuel, a full-sized spare tire, and portable oxygen, as a breakdown at 4,905 meters is a high-isolation emergency where the thin air makes any physical effort, like changing a tire, an exhausting task.
Road suggested by: Hugh Wilson
Pic&video: Ruben Goicochea