High in the department of Nariño, in Colombia's far southwest, the land folds into deep canyons cut by the Guáitara River, and the old Inca road, the Qhapaq Ñan, threads along the slopes. Rosal de Chapal is one of the surviving fragments of that road on the Colombian side, a stretch of track near the small towns of Funes, Iles and Contadero. The Qhapaq Ñan, a network of roads that tied the Inca empire together from present day Colombia to Chile and Argentina, was inscribed as a World Heritage Site in 2014, and Nariño holds its northernmost sections.
It is easy to underestimate how high you are. These are the Andes at around three thousand metres, with cold mornings, strong sun and air that saps energy on a walk. The fields are a patchwork of potatoes, barley and pasture climbing improbably steep slopes, with eucalyptus windbreaks and adobe houses. Clouds boil up from the canyons in the afternoon, and rain can turn dirt tracks to grease fast.
The riding here is serious. Main roads in Nariño are paved but busy with trucks and buses, with sharp bends, landslide scars and sudden potholes, while the side roads toward the canyon villages are often unpaved, steep and rutted. A light bike and good tyres make sense, and so does riding in daylight only. The descent into the Guáitara gorge and the climb out again are spectacular, but give them time.
Not far south, the sanctuary of Las Lajas near Ipiales is built across the Guáitara canyon itself, a neo-Gothic church on a bridge over the river, and it is one of the great sights of southern Colombia. Funes is known for its canyon and for the road between Pasto and Ipiales passing through the region. Local food runs to hearty soups, roast guinea pig, cuy, which is a regional speciality, and hot drinks to fight off the chill.
Funes and Iles are small towns of a couple of thousand people with shops but limited services; do not count on fuel there. Pupiales, about twenty kilometres away, and especially Ipiales or Pasto are where to fill up and find reliable food and lodging. Carry water, warm layers and a rain cover, and check local advice on road conditions before heading down any canyon track.