El Calafate to Cerro Castillo

The route then turns to the southeast and tackles a MASSIVE ascent. Despite the duration of the climb (~20 km), a low gradient + pavement make the ascent manageable. Take a break at the top to enjoy phenomenal views of Lago Argentino and the Río Santa Cruz valley.

After the massive climb, the route turns to the south and proceeds downhill through open pampas. Tailwinds are common on this stretch of Ruta 40 and it's possible to cover major distance in just a short time.  Look west for Cerro Pináculo and its neighboring mountains.

The route soon passes some semblance of civilization: an AGVP building. AGVP is a road support network provided by the Santa Cruz provincial government and tasked with maintaining and serving remote stretches of road. Be polite and AGVP will usually be happy to provide you with water (hot water too!) and a place to camp that's protected from the wind. At this AGVP building, the road forks. To continue on Ruta 40, veer right (south) onto the ripio road. For the longer (paved) route, continue straight onto Ruta 5.

The Ruta 40 ripio option is shorter; however, beware! If it's raining, this section of road can produce thick mud.  There is a police station after ~20 km which can provide some protection from the wind and an estancia approximately halfway between El Cerrito and Tapi Aike — ask the gauchos at the estancia for permission to stay or fill your canteens.  South of the estancia, the condition of the ripio worsens.  A few kilometers before Tapi Aike, the route passes a small lake where flamingos can be spotted. Tapi Aike is comprised of an AGVP building, police station and a tiny gas station, which is often diesel-only. Behind the Tapi Aike AGVP building there is a garden that is protected from the wind that is an ideal spot for tent-camping.

South of Tapi Aike, pavement recommences as the route heads southwest toward Chile.  After ~13 km, the road forks: stay left for pavement (more vehicle traffic) or veer right onto ripio. Assuming you choose the paved option, after ~25 km turn right onto the ripio road. There is no sign here - look for garbage cans on the corner.*

*A note from Bicycle Patagonia: Given the proximity of Torres del Paine and the border crossing to this intersection, a reasonable person might expect that Santa Cruz would put a sign here, right? Wrong. There is no indication that travelers should swing a right for the Chilean border/Torres del Paine. Yet another case of the Argentine government showing disregard for a road leading to the Chilean border... (remember the terrible ripio between Trevelin and Futaleufú?)

Pedal by the tiny community of Cancha Carrera and to the border crossing. Same drill as last border crossing: don't forget to collect your exit stamp from the Argentine border control office. The ride between the two border crossing stations is ~8 km. As of 2017, this road is undergoing construction. Remember: Chile has strict restrictions on what kinds of food/animal products you can bring into the country, so ditch (or eat) all your contraband (produce, animal products, honey!) before crossing the border.