Cerro Castillo to Puerto Natales

Lago Sarmiento is a great area to view condors and there is a nice shelter where you can stop for a break or lunch. Continue northwest and loop around Lago Sarmiento, before turning west and descending toward Laguna Amarga and the towering Torres.  This area is a favorite spot for herds of guanacos.  Just beyond Laguna Amarga is the park's northern entrance. This entrance is staffed starting at 07:00 —  entrance fees are collected at the gate.  The road transitions to ripio just before the park entrance.

Beyond the park entrance, the road forks. Stay left (southwest) to proceed through the park. Alternately, take a right (north) for one of the park's principal trailheads. As you pedal through the park, there is an immediate climb — the toughest of the route.  Caution: this mountainous area is a hotspot for pumas, especially around dawn and dusk.

Enjoy breathtaking scenery and easily-visible wildlife as you make your way through the park on ripio that is in OK condition – be sure to look out for dwarf armadillos as you pass Lago Pehoe! Vehicle traffic is moderate, prepare to be ogled by tourists gazing from the windows of passing tour vans. After tracing the east shore of Lago Pehoe, the route continues south through grasslands, past the park's southern entrance, then across Río Serrano.

South of the park, pavement recommences as the route briefly turns northeast, before reaching the shore of Lago el Toro. Enjoy a tailwind and spectacular views as you climb alongside the massive lake, then descend toward Lago Porteño (where there is a great wild camp spot).

Pedal by the towering peak of Cerro Tenerife (to the west) and continue southwest through a quiet valley. The route ascends to the Milodón Caves (the home of a prehistoric giant sloth-like creature) where pavement recommences.

Onward to Puerto Natales! Y-290 turns directly east then intersects with Ruta 9.  Turn right and head south on "La Ruta de fin del Mundo".  Traffic is much heavier here and the shoulder is sometimes be narrow (especially at the crest of each rolling hill).  Pass the Puerto Natales airport then navigate alongside Seno Última Esperanza (Sound of Last Hope) and into Puerto Natales.