Route 40: how to read the map before you go
What Argentina's Route 40 is, which Patagonian stretches are paved or gravel, and how people reach El Calafate and El Chaltén.
General travel guide. It does not describe rental terms.
The country's spine
National Route 40 runs the length of Argentina, and in Patagonia it is the road everyone means by a southern road trip. It is not one kind of road: depending on the stretch it is a divided highway, two-lane pavement, or long gravel.
Plan it in stages and check the surface of the stretch you will actually drive. The same route number changes surface more than once.
Patagonia: pavement and gravel
In northern Patagonia there is usable pavement between Neuquén and the lake district. Farther south, the central Santa Cruz stretch — Tres Lagos, Gobernador Gregores, Bajo Caracoles, and the town of Perito Moreno — has long gravel sections and corrugation.
That gravel core is not a footnote: it adds time and asks for a vehicle suited to the surface. This note does not say which rental vehicles may use it.
El Calafate and El Chaltén
The local access to El Calafate, the Perito Moreno Glacier, and El Chaltén is paved. The usual way in from the south is Atlantic Route 3 to Río Gallegos and then pavement toward the lakes, not the central gravel of Route 40.
Most travelers use November to March for that far south. Outside that window it is colder, snow shows up, and many services shorten their hours.