The Most Remarkable Rock Formations in South America
7 places in 6 countries · updated 13 October 2026
In short: By our ranking, the most remarkable rock formations in South America are Valle de la Luna, Atacama (Chile), Vale da Lua (Brazil) and Árbol de Piedra (Bolivia). The list covers 7 rock formations in 6 countries. Argentina has the most, with 2. Last updated 13 October 2026.
South America's rock formations are shaped by two great forces: the volcanoes of the Andes, which buried highland plateaus under ash, lava and pumice, and the dry winds of the Atacama and the Altiplano, which have been sanding that rock into strange forms ever since. Little rain falls to soften the shapes or cover them with plants, so the sculpture stays sharp. Farther east, older crystalline rocks of the Brazilian highlands are polished by rivers rather than wind.
The Valle de la Luna near San Pedro de Atacama is a landscape of salt-crusted ridges, dunes and clay pinnacles in one of the driest places on Earth. On the Bolivian Altiplano, the Árbol de Piedra rises from the sand of the Siloli Desert as a slender column of volcanic rock widening into a crown, carved by wind-blown grit. In Argentina's Catamarca province, the Campo de Piedra Pómez is a vast field of white and pinkish pumice cut by the wind into ridges and hollows.
Puente del Inca, high in the Andes near Mendoza, is a natural bridge over the Las Cuevas River, stained yellow and orange by mineral-laden hot springs; Charles Darwin described it in 1835. Ecuador's Nariz del Diablo is a near-vertical rock wall that the Guayaquil–Quito railway climbs by a series of switchbacks cut into its face. In Brazil, the Vale da Lua in Chapada dos Veadeiros is a river channel of rock smoothed into potholes and crater-like basins.
In this list
| # | Place | Type | Country | UNESCO |
|---|---|---|---|---|
| 1 | Valle de la Luna, Atacama | Rock formation | Chile | |
| 2 | Vale da Lua | Rock formation | Brazil | |
| 3 | Árbol de Piedra | Rock formation | Bolivia | |
| 4 | Puente del Inca | Natural arch | Argentina | |
| 5 | Nariz del Diablo (Devil's Nose) | Rock formation | Ecuador | |
| 6 | Campo de Piedra Pómez | Rock formation | Argentina | |
| 7 | Huayllay Stone Forest | Rock formation | Peru |
01 Valle de la Luna, Atacama
Valle de la Luna
Chile22.911° S 68.323° W
Image by rumpelstilzken from Pixabay The salt range itself was born when movements of the Earth's crust pushed up and folded ancient lake and sea deposits, layers of salt, gypsum and clay that now stand on edge for about a hundred kilometres. In a climate where rain is extremely rare, wind and the occasional flood have worked these soft layers into strange forms. White salt crusts on the ground look like frost or snow, and some of the ridges are cut by narrow canyons and caves.
Did you know? More than 50 salt caves riddle the range, some over 2 km long, nearly all carved within the last 6,000 years by rare desert downpours.
02 Vale da Lua
Brazil14.187° S 47.790° W
Cristiamara Giordani · CC BY-SA 4.0 The sculpting is the work of the river itself. Over an immense span of time, pebbles and sand carried by fast-flowing water have been spun in eddies against the rock, drilling cylindrical hollows that merge into one another as they deepen and widen. The bedrock belongs to the very old metamorphic formations of the Chapada dos Veadeiros, a high plateau whose rocks date back well over a billion years and are dominated by quartzites that began as sediments on an ancient sea floor. Where softer, more soluble material was mixed into the rock it was removed faster, adding to the irregular, honeycombed texture of the surface.
Did you know? Each pothole starts as a whirlpool that traps pebbles, which then spin and grind the riverbed like a drill.
03 Árbol de Piedra
Bolivia22.052° S 67.883° W
Image by sgrunden from Pixabay The rock is a ventifact — a form carved by wind-blown sand. On this exposed plateau strong winds drive grains of sand close to the ground, and over time the soft rock has been worn away much more at its base, leaving the narrow trunk and wide head. The Stone Tree stands among other eroded outcrops protruding from the sand dunes of the Siloli desert.
Did you know? The reserve around the Stone Tree is named after Eduardo Abaroa (1838–1879), a Bolivian national hero of the War of the Pacific.
04 Puente del Inca
Argentina32.827° S 69.911° W
Image by magicaltravelling from Pixabay Its origin combines ice and hot water. During the ice ages, glaciers left great piles of rubble in the valley; mineral-rich water from the springs seeped through the debris and cemented it into solid rock. The river then cut a channel through the weaker lower layers, leaving the hardened upper part standing as a bridge. Charles Darwin crossed this way in March 1835 and sketched the bridge with its long stalactites hanging from the underside.
Did you know? The springs flow at roughly 34 to 38 °C, and they are among the highest-altitude thermal springs in Argentina.
05 Nariz del Diablo (Devil's Nose)
Nariz del Diablo
Ecuador · 6.6 km from Alausí2.243° S 78.877° W
Carine06 · CC BY-SA 2.0 The Devil's Nose is the most dramatic stretch of Ecuador's railway between Guayaquil and Quito, begun in 1899, completed in 1908 and regarded at the time as a feat of engineering. The southern part of the route rises from the coastal lowlands at Durán, opposite Guayaquil, through Bucay at about 300 metres to Sibambe at around 1,800 metres, then on up to Alausí at 2,360 metres and Riobamba at 2,754 metres, crossing several climate zones on the way. The zigzag at the Nariz del Diablo accounts for a large share of that climb, gaining height on a cliff where a conventional line could find no room.
Did you know? Thousands of labourers were recruited from Jamaica around 1900 for this stretch, and estimates of the workers who died building it run into the thousands.
06 Campo de Piedra Pómez
Argentina26.660° S 67.514° W
Rodolfo Pace · CC BY 2.0 The rock is young by geological standards. Around 4,200 years ago Cerro Blanco produced one of the largest eruptions of recent millennia in the central Andes, spreading roughly 170 km³ of ash and pumice over some 500,000 km² — the layer is still about 20 cm thick in Santiago del Estero, 370 km to the east. The field itself lies on an older ignimbrite sheet from earlier eruptions of the same volcanic system, laid down tens of thousands of years before. That soft, porous deposit is the raw material of the field.
Did you know? That eruption was larger than Peru's 1600 Huaynaputina eruption, the biggest volcanic event recorded in the region's history.
07 Huayllay Stone Forest
Bosque de Piedras de Huayllay
Peru · 35.9 km from Cerro de Pasco11.000° S 76.366° W
Jomel Contreras Espinoza · CC BY-SA 4.0 The rock began as volcanic ash. Early in the Cenozoic, eruptions laid down thick sheets of ignimbrite — ash welded into stone — on top of older sandstone, limestone and conglomerate, forming a high plateau. Ignimbrite is porous and easily attacked, and during the last ice age, roughly 20,000 years ago, repeated freezing and thawing drove water into every crack, prising the rock apart. Wind, water and ice then carved what remained into the free-standing figures seen today.
Did you know? More than 4,000 rock formations stand in the forest, and local people have given names to roughly 480 of them.
How this list is ranked
Places are chosen for how they look, not for how famous they are: each one has its own description and a photograph credited to its author. The order is a single world ranking that weighs the beauty of the place in curated photography together with how widely it is documented — the number of language editions of its encyclopedia article and how often that article is read in a year. The list is rebuilt as places are added, so the order and the counts on this page are always current.
Questions people ask
- What are the most remarkable rock formations in South America?
- On our list, Valle de la Luna, Atacama (Chile) ranks first, followed by Vale da Lua (Brazil) and Árbol de Piedra (Bolivia).
- Which country has the most rock formations in South America?
- In our collection, the most come from Argentina (2), Bolivia (1) and Brazil (1).
- Why is the Valle de la Luna called the Valley of the Moon?
- Its bare ridges of salt, clay and sand, with no vegetation and almost no rain, resemble a lunar surface. The valley lies in the Cordillera de la Sal near San Pedro de Atacama in northern Chile.
- How was the Árbol de Piedra formed?
- Strong winds carrying sand across the Siloli Desert wore away the softer lower part of a volcanic rock outcrop faster than the top. The result is a column about seven metres tall with a thin stem and a wider crown, like a stone tree.
- What is the Devil's Nose in Ecuador?
- It is a steep mountain wall near Alausí that the railway between Guayaquil and Quito overcomes by a series of zigzag switchbacks cut into the rock, completed in the early twentieth century.
- How many rock formations are on this list in South America?
- The list covers 7 rock formations in 6 countries. Argentina has the most, with 2.