The SC-390 highway does not so much climb the serra as zigzag up its wall. Linking Lauro Müller at the foot to Bom Jardim da Serra on the plateau, the modern road was inaugurated in 1960 after a punishing feat of engineering, and its most famous stretch coils through a tight band of hairpins to overcome a drop of more than a thousand meters. The Santa Catarina infrastructure authorities count hundreds of sharp curves packed into a few kilometers, a density that has earned the road a reputation among drivers who collect such things. Photographs taken from the upper lookouts show the asphalt doubling back on itself so many times it looks less like a route than a coiled spring laid against the mountain.

Altitude rewrites the climate as you ascend. The highest point of the range stands at 1,460 meters above sea level, high enough that frosts are common through the colder months and snow can fall on the upper reaches, a rarity that draws Brazilians north and south to chase it. The ride takes you from humid Atlantic Forest near the base, green and dripping, up through cloud and into open highland where the wind cuts and the vegetation thins to grass and scattered shrubs. In a single morning a traveler can leave a subtropical coast and arrive somewhere that feels, briefly, like a different country at a higher latitude.

The cliffs are not just scenery; they are a cross-section of the planet's past. These layers lend their name to the Rio do Rasto Formation, a band of ancient rock laid down some 260 million years ago in the Permian, when this part of Gondwana held river floodplains rather than mountains. Erosion has since carved the strata into the deep escarpment seen today, exposing the colored bands like pages in a book. The wildlife that lives among them includes the coati, a long-tailed, ring-marked relative of the raccoon often seen nosing along the lookouts at the summit, unbothered by the drop or the visitors leaning out to photograph the sea.

Travelers come for the mirantes, the overlooks ranged along the upper road, where on a cloudless day the view runs unbroken from the highland down the folded asphalt to the distant glint of the Atlantic. When the clouds roll in, and they often do, the spectacle changes entirely: the lowlands vanish under a white sea of fog, and the road seems to descend straight into nothing. Either way the serra makes the same point. Few places let you watch a road wrestle with a mountain so plainly, every curve a small argument between human engineering and a wall of rock that would rather not be crossed.