The oldest radiocarbon date from the Lavapatas site - 3300 ± 120 BC - places the beginnings of San Agustín culture in the thirty-third century BC. That makes this one of the deepest continuous cultural sequences in South America. Archaeologists divide it into four periods: Archaic (before 1000 BC), Formative (1000-600 BC), Regional Classic (1-900 AD), and Recent (900-1350 AD). During the Archaic, groups of 15 to 25 people moved seasonally through the mountains using wild crops and stone tools similar to those of the Calima Valley and Popayán. By 1000-600 BC sedentary villages had grown along the fertile slopes. Ceramics appeared. The dead were already being buried in shaft tombs near their houses. The real flowering - the megaliths and the gold - came later.

The peak of San Agustín culture appears to have fallen between the 8th and 1st centuries BC, though monumental statues continue into the Regional Classic Period (1-900 AD). In that long window, carvers quarried volcanic tuff and andesite from the Colombian Massif and dragged blocks weighing several tons up onto ridges of the Magdalena headwaters. Large earthen mounds, some 30 meters across and 5 meters tall, were raised over dolmen tombs of slab-walled chambers. The statues that stand guard at the entrances are called caryatids because they once supported the heavy stone ceilings of the great tombs at Mesitas A and B. The tomb offerings are sparse - these cultures spent their wealth on the statues themselves and on elaborate gold work that contrasts strangely with the rough pottery.

In a rocky ravine bed, water still runs over the most remarkable single work of the San Agustín carvers: the Fuente de Lavapatas, a ceremonial fountain carved directly into the bedrock. Three pools step down the channel. Between and around them, serpentine and frog-like figures in low relief writhe through a web of tiny water channels. When the river runs normally, water flows over all of it - through the mouths of the creatures, into the pools, between the relief figures. Archaeologists interpret the site as dedicated to aquatic deities and healing ceremonies. It is one of the few places in the Americas where a culture carved a permanent interactive artwork directly into living rock - a piece meant to be seen running, not still.

The religious imagery of San Agustín is consistent across a thousand years of carving. The sun, moon, lightning, and rain appear repeatedly in anthropo-zoomorphic form, deities personified as part-human, part-animal figures closely tied to mortuary rites. The most common single motif is the feline mouth - the fanged, snarling upper lip that archaeologists call the jaguar mouth. It is not unique to this culture; the cult of the jaguar is among the oldest and most widespread religious motifs in the Andean and Amazonian world, and it persists today among indigenous peoples of the Amazon. But at San Agustín the feline mouth dominates the sculptural record, appearing on warrior statues, mortuary guardians, and smaller reliefs. The deities carved here were born of a theology that predates writing in South America.

By the 14th or 15th century AD - just before the Spanish arrived - the people who had built these monuments had left. The Recent Period saw population growth, intensified agriculture, drainage channels, and retaining walls. Then, without evident catastrophe, the statue-builders stopped building. The tombs stopped receiving new burials. Small family groups, linked by religious ties, may have been the social unit all along; archaeologists suspect that a loose confederation of such groups, possibly led by shaman-chieftains practicing what some writers call mohánismo, held the whole system together. When that web unraveled, the stone figures stayed where they had been placed, the ceremonial fountain kept running water through the carved mouths of its serpents, and the forest closed in. A sister culture at Tierradentro, to the west, followed a related path. In 1995 UNESCO recognized the San Agustín Archaeological Park as a World Heritage Site. More than 300 of the stone figures now stand protected in the parks at San Agustín, Isnos, and Saladoblanco in Huila Department - a congregation of lithic warriors, jaguars, priests, and mothers, still waiting, still arranged as their makers left them.