Ripple marks and tufa deposits around the entrance tell the cave's geological origin story. A waterfall once poured through this passage, carving the dolomite tube before receding and leaving the space habitable. The cave sits within the Leba-Tchamalindi Formation, a geological unit rich in siltites, cherts, and fossil stromatolites, with mineral deposits dating from the Miocene to the Early Holocene. The fractured, fissured bedrock created natural shelves and recesses where sediments accumulated over millennia, trapping the artifacts and animal bones that would eventually draw archaeologists. For the early humans who used it, Leba Cave was likely a waypoint rather than a home. Researchers believe it served as a periodic refuge for people moving between the arid coastal lowlands and the forests of the Humpata Plateau, a shelter for the night rather than a settlement for the season.

Leba Cave entered the archaeological record almost by accident. In 1947, workers building lime kilns for the Fazenda da Leba factory stumbled upon the site. By 1950, the archaeologist Raymond Dart reported that Portuguese colleagues had already been studying fossiliferous breccia removed from the cave years earlier. That same year, Jose Camarate-Franca conducted the first formal excavation during the Anthropobiological Mission of Angola. He returned in 1951 and 1953, but produced only a four-page report before his death in 1963, leaving a longer manuscript unfinished. In 1966, John Desmond Clark published descriptions of 28 Middle Stone Age lithic tools from the site. Victor Oliveira Jorge led a smaller dig in 1974, but the detailed records of his work have been lost. Then the Angolan Civil War shut everything down. For over four decades, the cave sat unstudied, its secrets locked in sediment while the country tore itself apart above.

The archaeology of Leba Cave reads like an inventory of southwestern African wildlife. Zebras, antelope, rhinoceros, warthog, and buffalo are all represented in the bone assemblages, alongside baboons and various birds. A domestic dog dating to the colonial period turned up as well, a reminder that the cave's story did not end with the Stone Age. Some bones show evidence of human modification or fire exposure. Others bear the tooth marks of predators. At certain periods, the cave was occupied not by people but by lions, leopards, and hyenas, the evidence visible in gnaw marks and predation damage on the recovered remains. One find stands out for its sheer strangeness: paleontologist Eli Minkoff hypothesized that trauma observed on a baboon skull may have been inflicted by an australopithecine, a claim that, if confirmed, would push the human story at Leba Cave back millions of years.

In February 2018, new excavations began under the direction of Daniela de Matos, ending a hiatus that had lasted since the 1970s. The gap is a reminder of what war costs beyond the obvious toll. Decades of potential discovery were lost, field notes vanished, and the continuity of scholarship was severed. De Matos and her team now work with modern techniques that Camarate-Franca and Oliveira Jorge could not have imagined, but they also work with the knowledge that the site has been disturbed by decades without stewardship. The cave itself endures, indifferent to the interruptions. Its chert and quartz still litter the floor and the surrounding riverbed. The dolomite walls still hold the ripple marks left by the waterfall that created the passage. Somewhere in the remaining sediment, more of Angola's deep human history waits to be read.