El Centinela, Summit in Tandil, Argentina

El Centinela is a summit 5 km from Tandil, Buenos Aires Province, Argentina, rising to 298 m above sea level. Its name comes from the rock silhouette that crowns it. The summit rock has a concave, smoothed southeast face shaped by prevailing winds and a convex, rough northwest face where solar exposure and reduced wind limit erosion.

The hill's name comes from the rock silhouette crowning it, and its Mapuche legend tells of Amaike, daughter of a chief, who drowned in a stream after escaping the fort. Her lover Yanquetruz waited on the summit until the Sun placed her spirit in the rock. The area was later taken during the Conquest of the Desert.

The name comes from the rock silhouette crowning the hill, which resembles a sentinel. A Mapuche legend tells of Amaike, daughter of a chief of the Tandil sierras, a skilled rider who was captured and drowned in a stream; Yanquetruz waited for her on the hilltop until the Sun, creator of the Puelches, placed his spirit in the rock so her soul could be freed and their love continue in a second life.

The hike to the summit takes roughly two hours on a well-marked trail starting from the parking area at the base. Wear sturdy shoes and bring water, as the route crosses rocky ground and gains elevation steadily.

The rocky silhouette crowning the hill gives El Centinela its name. Its southeast face is concave and smoothed by the prevailing winds, while the northwest face is convex and rough, an example of exfoliation erosion the source calls "cáscara de cebolla".