Chankillo

Chankillo is an archaeological complex in the Ancash region of coastal Peru known for its ancient solar observatory. The site combines a fortified settlement and a long row of towers that function as an astronomical installation.

The site’s most striking element is a linear series of thirteen towers along a ridge that form precise sightlines to the horizon and mark the sun’s annual positions. The tower row extends roughly 300 metres and is paired with viewing points and platforms at either end, allowing observers to track sunrise and sunset positions through the year.

Excavations show the complex included defensive walls, terraces and domestic structures clustered behind the towers; together these elements suggest Chankillo served both ceremonial-astronomical and settlement functions. Archaeological dates place the main construction and use in the first millennium BCE, attributed to coastal pre-Columbian cultures.

Chankillo sits on a ridge in the Casma Valley of Ancash on Peru’s arid coastal plain, above nearby valley farmland and within travel range of the modern town of Casma. The remains are visible from the surrounding desert landscape and require on-site approach over unpaved roads.

• Date and use: Built around the first millennium BCE and in use by local coastal cultures as an astronomical and ceremonial landscape.
• Solar alignment: The 13 towers form a deliberate horizon calendar - alignments mark solstices and intermediate solar positions across about 300 metres of ridge.

What to See#

• Thirteen Towers: A linear row of 13 stone towers aligned along a ridge used as a solar observatory; the row is roughly 300 metres long and the towers stand several metres high, creating marked sightlines to the horizon.
• Fortified complex: A fortified hilltop complex with defensive walls, terraces and residential structures that sits immediately behind the tower alignment and includes platforms and building foundations.
• Observation points: A series of low-lying viewing platforms and sighting points at either end of the tower row used to mark sunrise and sunset positions on the horizon throughout the year.

Chankillo is reached from the nearby coastal town of Casma in Ancash. Long‑distance buses on the Panamericana Norte (the coastal Pan‑American Highway) serve Casma from larger Peruvian cities; from Casma you should take a taxi or local colectivo to the archaeological site (short local drive and a brief walk from the access road).

• Visit at sunrise or late afternoon to see the Thirteen Towers' solar alignments and to get the best light for photos while avoiding the midday heat common in the Ancash valley.
• Approach from the Pan‑American Highway via Casma and allow time for the short walk from the roadside parking-there is no large visitor infrastructure at the ruin itself, so plan logistics from Casma.
• Hire a local guide from Casma or the nearby towns for archaeological context and to help interpret the tower alignments and nearby ruins; guided visits make the sparse signage easier to understand.