Cañón del Pato

North of Caraz the Santa river cuts between the Cordillera Blanca and the Cordillera Negra into a gorge that closes to a few metres wide, and the road built through it - originally a railway alignment - runs in and out of around thirty-five tunnels hacked through solid rock, some unlit, most single lane, with the river directly below and rock walls close enough on both sides to touch from a vehicle window. The name, Duck Canyon, comes from the shape of the narrows. The gorge holds a major hydroelectric plant at Huallanca, exploiting the drop, and the road continues to Chimbote on the coast, making this the dramatic route between the Callejón de Huaylas and the sea. It is not a place to stop and walk; the experience is the drive, and it is genuinely alarming in a full-size bus meeting oncoming traffic inside a tunnel.

What you actually see

• The tunnels - around thirty-five cut through rock, many unlit and single lane.
• The narrows - a gorge that closes to a few metres between vertical walls.
• The Santa river - directly below the road for most of the route.
• The hydro plant - Huallanca, built to use the drop through the canyon.

When to go

May to September. Landslides and rockfall close the road, and it is worse in the rains. Two to three hours between Caraz and Huallanca.

Honest expectations

Single-lane unlit tunnels with two-way traffic and long drops - people find this frightening, and accidents happen. Nowhere safe to stop for photographs along much of it. Dust and roadworks. Not a walking destination.

Nearby

Caraz and Laguna Parón are south; Chimbote and the coast are west.