🇵🇪 Peru · The Coast
In the Casma valley, where the desert of the north-central coast opens out between arid hills and farmland, hides one of the oldest and most unsettling puzzles in Peru: Cerro Sechín. Its walls are faced with large stone slabs carved with figures of warriors, severed heads and mutilated bodies, a stone frieze thousands of years old that still baffles archaeologists. It's a trip back to the very origin of Andean civilization.
Sechín isn't alone: the Casma valley is one of the most extraordinary and least known archaeological areas in Peru. A few kilometers away stands Sechín Bajo —where some of the oldest monumental structures in all the Americas have been found— and, further on, the imposing fortress of Chankillo, with its Thirteen Towers, recognized as the oldest solar observatory on the continent and declared a World Heritage Site. A whole valley that tells the story of the first great temples of the Andes.
This guide covers the essentials of Sechín and the Casma valley with a practical eye: what admission actually costs, what to see at each site, how to get there, how to organize the visit from Casma and how to combine it with the nearby beaches or with the route toward Huaraz. A destination for anyone who loves archaeology and the great mysteries of the past, in a region where the history of Peru begins long before the Incas.
Cerro Sechín is one of the oldest temples in Peru and in the Americas, raised several thousand years ago in the Casma valley, on the north-central coast. It belongs to the so-called Sechín culture (or Casma valley cultural complex), one of the formative societies that, long before the Incas, built large ceremonial centers in the Andes. The site's most celebrated feature is its outer wall, faced with monoliths and stone slabs carved with reliefs of armed warriors and mutilated human bodies —severed heads, entrails, cut-off limbs—, a dramatic iconography whose exact meaning is still debated: for some it depicts a battle or a sacrifice, for others a ritual procession or a message about power. The site was found and studied in the 20th century by the Peruvian archaeologist Julio C. Tello, considered the 'father of Peruvian archaeology'. The Casma valley holds other key sites: Sechín Bajo, where structures counted among the oldest in the Americas were found; the extensive Sechín Alto; and, somewhat later, the fortress and solar observatory of Chankillo, with its Thirteen Towers, declared a UNESCO World Heritage Site. Together they make the Casma valley a unique window onto the dawn of Andean civilization. The full story is on our history page.
Read the full history ↓The region of the snow-capped summits: between the Cordillera Blanca —the highest in the tropics— and the Callejón de Huaylas, home to Huascarán, to the temple of Chavín, to the avalanche that buried Yungay and to turquoise lakes.
Read the history of Áncash →No exact prices: a scale from $ (budget) to $$$$$ (luxury), with 2-3 options per category.
Origins, formation and what the sources say.
To understand Sechín you have to look at the whole valley around it. The Casma valley, on Peru's north-central coast, is one of the most extraordinary settings for the birth of civilization in the Andes. Here, several thousand years ago, some of the first complex societies in all the Americas took shape, able to organize collective labor to raise large monumental buildings for ceremonial purposes.
This wasn't an isolated phenomenon: it happened alongside other centers on the north-central coast, such as the nearby Supe valley, where Caral developed, considered the oldest civilization in the Americas. The Peruvian coast, with its valleys watered by rivers coming down from the Andes into an extraordinarily rich sea, offered the conditions for populations of fishers and farmers to settle, grow and build the first great temples on the continent.
In the Casma valley, that ancient history left an exceptional group of sites: Cerro Sechín, with its famous reliefs; Sechín Bajo, with structures among the oldest in the Americas; the extensive Sechín Alto; and, somewhat later, Chankillo, with its solar observatory. Together they make the valley a unique window onto the dawn of Andean civilization, long before the Incas.
Cerro Sechín is a pre-Inca temple raised several thousand years ago, which puts it among the oldest monuments in Peru and in the Americas. It belongs to the so-called Sechín culture (or Casma valley cultural complex), one of the formative societies of the north-central coast that built large ceremonial centers at a very early point in Andean history.
The core of the site is a stepped structure that, across different building phases, was enlarged and remodeled over time, as was usual in ancient Andean temples, which were rebuilt on top of themselves. What sets Cerro Sechín apart from other temples of its era is the decoration of its perimeter wall: instead of the modeled clay reliefs or the paintings seen at other sites, here the builders faced the wall with large carved stone slabs and monoliths.
That choice —carving stone to depict scenes— makes Sechín a singular and especially striking case. Standing in front of its walls means looking at one of the oldest expressions of monumental stone art in the Andes, a direct record of the beliefs and the power of one of the continent's first civilizations.
The great mystery of Cerro Sechín is the reliefs on its outer wall. The large stone slabs show, in a sequence running around the temple, two kinds of figures alternating: on one hand, leading personages —often read as warriors or priests— standing, armed, with headdresses and dress that mark their rank; on the other, mutilated human bodies rendered with striking rawness: severed heads with closed eyes, spinal columns, entrails, cut-off arms and legs, drops of blood.
What these scenes mean has been debated at length. Some archaeologists read them as commemorating a battle or a ritual sacrifice: the victors or the sacrificers, standing, beside the defeated or the victims, dismembered. Others suggest it's a ceremonial procession, or a message meant to display the power of those who ran the temple and to inspire respect or fear in anyone looking at it. There are even readings that see the bodies as mythical or medical depictions.
No explanation is definitive, and that ambiguity is part of the pull of Sechín. What's certain is that the reliefs carry a message loaded with violence, power and ritual, fitting for a society able to build great temples and to set an unsettling iconography in stone, thousands of years before the Incas.
Modern knowledge of Cerro Sechín is bound up with Julio C. Tello, considered the 'father of Peruvian archaeology'. Tello, of Andean origin and scientific training, spent his life studying and vindicating Peru's oldest civilizations, showing that the greatness of Peruvian history didn't begin with the Incas but much earlier, with formative cultures of enormous antiquity.
In the 20th century, Tello investigated the site of Cerro Sechín and made its extraordinary reliefs known, placing it within the panorama of the great early cultures of the Andes. His work at Sechín, along with his studies at Chavín de Huántar and other sites, was key to reconstructing the sequence of ancient Andean civilizations and to placing Peru's coast and highlands among the original centers of civilization in the Americas.
Thanks to that research, Cerro Sechín went from being a set of enigmatic stones to a fundamental site for understanding the origins of Peru. Today the site museum pays tribute to Tello and helps visitors grasp the context and importance of the temple within the long history of Andean cultures.
In the same valley, the site of Sechín Bajo has produced one of the most significant finds in American archaeology. Excavations there revealed monumental structures —among them a sunken circular plaza— whose age places them among the earliest known constructions of their type anywhere on the continent, going back thousands of years toward the beginnings of monumental architecture in the Andes.
The discovery reinforced the idea that the Casma valley was one of the places where, very early on, societies emerged that could plan and build large-scale ceremonial spaces. The presence of a sunken circular plaza —a type of ritual space that would recur in later Andean cultures— also shows the continuity of certain architectural and religious ideas across millennia.
Sechín Bajo, along with Cerro Sechín and nearby Caral, is part of the group of sites that have pushed back the date for the birth of civilization in the Americas and placed Peru's north-central coast at the center of that great chapter of human history. Visiting it means standing in front of the very origin of monumental architecture on the continent.
The Casma valley holds another extraordinary jewel, somewhat later than Sechín but just as exceptional: Chankillo. It's a wide complex that includes a walled fortress on a hill, buildings and, above all, the celebrated Thirteen Towers, a row of thirteen constructions lined up along a ridge. Seen from specific observation points, these towers marked with precision where the sun rose and set through the year.
Chankillo worked, then, as a solar calendar and observatory: by following where the sun appeared or disappeared among the towers, its builders could work out the seasons, the solstices and the equinoxes, information that was vital for a farming and ceremonial society. What's astonishing is its age: at more than two thousand years old, it's considered the oldest solar observatory in the Americas, proof of the advanced astronomical knowledge of Andean cultures.
For its unique value, the Chankillo Archaeoastronomical Complex was inscribed on UNESCO's World Heritage list in 2021. Together with Cerro Sechín and Sechín Bajo, Chankillo completes an exceptional valley that runs from the first monumental temples in the Americas to one of the oldest and most precise observations of the sky, all in the same landscape of desert and hills: the Casma valley, one of the great treasures of Peru's history.