Ruta 40 — properly National Route 40, or RN40 — runs roughly 5,194 km (3,227 miles) up the western edge of Argentina, from Cabo Vírgenes near Río Gallegos in Santa Cruz to La Quiaca on the Bolivian border in Jujuy. It is the longest route in South America, it parallels the Andes for its entire length, and it crosses 20 national parks, 18 major rivers and 27 Andean passes. Its highest point is the Abra del Acay in Salta Province. Almost nobody rides all of it in one go, and the useful question for a motorcyclist is not whether the whole thing is worth doing but which of its very different thirds you want.
The ride in one paragraph
RN40 crosses eleven provinces: Santa Cruz, Chubut, Río Negro, Neuquén, Mendoza, San Juan, La Rioja, Catamarca, Tucumán, Salta and Jujuy. In the far south it is a wind-blasted line across empty steppe with hundreds of kilometres between settlements. Through the Lake District around Bariloche it turns into some of the most pleasant touring road on the continent. In the northwest, above Cafayate and through the Calchaquí Valleys, it becomes a high-desert road of red rock and cactus that climbs to nearly 5,000 m. Construction began in 1935 and paving is still an ongoing national project, so the surface changes character province by province and year by year. Treat any single description of "the condition of Ruta 40" with suspicion, including this one — verify the section you are riding.
Route at a glance
| Road | Ruta Nacional 40 (RN40), Cabo Vírgenes, Santa Cruz to La Quiaca, Jujuy |
| Length | Approximately 5,194 km (3,227 miles), the longest route in South America |
| Provinces crossed | Eleven, from Santa Cruz in the far south to Jujuy on the Bolivian border |
| Highest point | Abra del Acay, Salta Province — 4,972 m (16,312 ft) per the pass's own record, though an old sign at the summit reads 4,895 m (16,060 ft) |
| Crosses | 20 national parks, 18 major rivers, 27 Andean passes |
| Remotest stretch | Perito Moreno to Tres Lagos, roughly 463 km with almost no habitation |
| Kilometre zero | Moved to Cabo Vírgenes by national resolution in November 2004 |
Open the length of Ruta 40 in Google Maps — Río Gallegos through Bariloche to La Quiaca, so you can send the outline to your navigation and then break it into legs.
The southern third, and the gap that matters
South of Perito Moreno the road enters the most remote part of its route, and the distances are worth writing down before you set off. It is 124 km (77 miles) from Perito Moreno to the junction with the side road to Cueva de las Manos, the cave-art site whose paintings date back some 13,000 years. Three kilometres further is Bajo Caracoles, a settlement of about a hundred people. Another 101 km (63 miles) brings the turn-off for Perito Moreno National Park. After that there is no habitation apart from a police station and, later, an estancia, until the small town of Tres Lagos some 235 km (146 miles) further south.
Add those up and you have roughly 463 km (288 miles) in which your fuel options are one village of a hundred people. Riders report carrying spare fuel through here as standard practice, and it is the right instinct. The steppe wind is the other feature: it blows persistently from the west across open ground with no shelter, and a crosswind that would be a novelty at home is simply the weather here for hours at a time. Plan shorter days than the map suggests.
Further south the road is paved from Tres Lagos to a junction 32 km (20 miles) east of El Calafate, which is where most travellers peel off for the Los Glaciares area before rejoining.
The middle third, and the Seven Lakes
North of Esquel the character changes completely. RN40 runs past Esquel and El Maitén towards Bariloche, and between San Martín de los Andes and Villa la Angostura it follows the Ruta de los Siete Lagos, the Seven Lakes route — forested, curving, paved and genuinely enjoyable rather than merely impressive. This is the section riders return for. It is also the busiest, and in January and February the towns along it fill with Argentine holiday traffic.
From Bariloche the road continues north through Zapala, Chos Malal and Malargüe to Mendoza, where RN40 becomes a busy trunk road on to San Juan. This is the pragmatic connecting section: covered efficiently, not lingered over.
The northern third, and Abra del Acay
Above San Juan, through La Rioja, Catamarca and Belén to Cafayate, the road turns into high-desert riding. North of Cafayate it threads the Calchaquí Valleys past Molinos and Cachi, then climbs towards San Antonio de los Cobres.
Between Cachi and San Antonio de los Cobres sits the Abra del Acay, the highest point on the entire route. The pass was inaugurated on 8 July 1960 after three years of construction and remains unpaved. The official description is blunt: this section is only suitable for all-terrain vehicles, except for some months of the year when weather and maintenance conditions allow normal vehicles through. The road gradient is around 4.5 per cent, which is not steep — the difficulty is altitude. Thin air costs a naturally aspirated engine a significant share of its power, and it costs the rider more than most people expect.
There is also a documented discrepancy worth knowing about: the pass's recorded altitude is 4,972 m (16,312 ft), while an older sign at the summit still states 4,895 m (16,060 ft). Either way you are close to 5,000 m on gravel, and that is not a place to discover you have altitude sickness.
Altitude, season, fuel and paperwork
Altitude. The northern section takes you from Cafayate at valley level to nearly 5,000 m within a couple of riding days if you push. That is faster than the body adapts. The general principle for high-altitude travel is to gain sleeping altitude gradually, spend a night or two at an intermediate elevation before going higher, drink far more water than feels necessary, and treat headache, nausea, breathlessness at rest or poor coordination as a signal to descend rather than to press on. Riding makes this harder to judge because you are sitting still while your body works. If you are planning Acay, build acclimatisation days into the schedule around San Antonio de los Cobres and talk to a doctor before you travel about whether preventive medication is appropriate for you.
Season. Argentina is in the southern hemisphere, so summer runs from December to February and winter from June to August. The southern steppe section is a summer proposition: long daylight, but also the strongest winds. The northern Puna has the opposite problem — its wet season falls in the southern summer, and rain on unpaved high-altitude roads means washouts and closures, which is exactly when Abra del Acay is least likely to be passable on anything but a serious off-road machine. Many riders therefore do the far south in December to February and the northwest in the drier months either side of winter. Check current status locally before committing, verified in August 2026 as still being the sensible approach.
Fuel. Stations exist in the towns and nowhere else. In the far south the 463 km Perito Moreno to Tres Lagos stretch is the classic problem; in the northwest the villages of the Calchaquí Valleys are small and supply is not guaranteed. Fill at every opportunity, carry spare fuel for the long legs, and remember that a station being marked on a map does not mean it has stock today.
Borders. RN40 ends at La Quiaca on the Bolivian frontier, and many riders cross into Chile at some point along its length. Carry your passport, home licence plus an International Driving Permit, the vehicle title or registration in your name, the temporary import permit from your entry, and insurance valid in the country you are entering. On a hired bike you need written authorisation from the rental company to take it across a border — without it you will be refused.
Gear notes for Ruta 40
The defining problem here is distance without infrastructure. Junctions in the steppe are unsigned, side roads to estancias look identical to the main line on a screen, and phone coverage is a town-only luxury. Loading the whole corridor in advance so your GPS navigation setup works without a signal is the baseline, and our notes on the risks of relying on a phone are especially relevant on a road where the next building is two hours away. Gravel sections plus 40-degree afternoons plus near-freezing nights at altitude move tyre pressures around considerably, so pair our tyre pressure guide with a TPMS setup that warns you about a slow leak before it becomes a roadside tyre change in a crosswind. Long days with no mains power make a bi-directional fast charger genuinely useful rather than a nice-to-have. If you are combining this with Chile, our Carretera Austral guide covers the road on the other side of the Andes, the Patagonia loop guide handles the southern crossings, and Ushuaia and the end of Ruta 3 covers where most riders finish.
FAQ
How long is Ruta 40 exactly?
Approximately 5,194 km (3,227 miles) from Cabo Vírgenes in Santa Cruz to La Quiaca in Jujuy. It is the longest route in South America. The figure has shifted over the years because sections of other highways have been absorbed into it and the zero-kilometre marker was moved to Cabo Vírgenes in 2004.
What is the highest point on Ruta 40?
The Abra del Acay in Salta Province. Its recorded altitude is 4,972 m (16,312 ft), though an older sign at the pass still reads 4,895 m (16,060 ft). The pass opened in 1960, is unpaved, and is officially described as suitable only for all-terrain vehicles except in certain months of the year.
Is Ruta 40 paved?
Partly. Paving has been an ongoing national project since construction began in 1935, and the southern part is now largely paved, but unpaved sections remain — including the Abra del Acay. Assume the surface varies by province and verify the specific section before you ride it.
Do you have to ride the whole thing?
No, and most riders do not. The three thirds are genuinely different roads: empty steppe in the south, forest and lakes around Bariloche, high desert in the northwest. Picking one and riding it properly is a better trip than rushing the lot.
When is the best time to ride Ruta 40?
The Patagonian south is a southern-summer ride, December to February, accepting that this is also the windiest period. The northwestern high desert has its rainy season in those same months, so the drier shoulder periods suit it better. Plan the two halves as separate seasons rather than one continuous trip.
