Tunel de Kahuish is a high mountain tunnel at an elevation of 4.516m (14,816ft) above the sea level, located in Ancash, a region of northern Peru. It’s one of the world's highest tunnels.
The tunnel is located within the Huascarán National Park, a national park in the Cordillera Blanca, a range of the Andes, in Ancash, and is traversed by the road AN-110, between Huaraz and Chavin. This road is usually open all year, but it can be closed anytime when the access is not cleared of snow. The tunnel lies on the the highest point on the main road and it’s said to be the longest tunnel in the country. It’s unlit. The tunnel was inaugurated in 1939 and improved in 2007. The tunnel is 483.67m (1,586.84ft) long. There’s no old road over the top of the ridge. Right behind the tunnel is a pretty impressive statue of Christ looking into the valley.
The road is mostly asphalted with some gravel sections. Road closures can be frequent, so check conditions before traveling to this area. Notorius lack of oxygen that tests the organisms and a high degree of steepness. Most people feel altitude sickness at around 2,500-2,800 meters. Extremely low oxygen for engine combustion. The tunnel leads through the valley of river Santa over the ridge of Cordillera Blanca to the valley of Marañon.