Chacabuco: dual gateway to history: this ghost town in Chile's Atacama Desert echoes sounds of a once-bustling nitrate business, as well as the cries of political prisoners of this former concentration camp.

• Author: Dinges, Tomas

The woman serving coffee at El Oasis truck stop and restaurant, located at the desert junction of the roads to Calama and Iquique, in the middle of the Chilean Atacama Desert, knows Roberto Zaldivar. He is the solitary man who lives in Chacabuco, the former nitrate town and detention center, a few miles away, and is a living memorial to the varied histories of this desert outpost. He would occasionally come in for a drink.

Outside the restaurant Sergio Venegas, an electrical engineer escorting an oversized transformer for a mining company, replies when asked that he has never heard of Zaldivar. But he knowingly points out the ninety-acre site on the barren horizon and offers a ride to a journalist seeking Chacabuco and its lone resident.

Pushing aside papers, maps, and bottles of water for his unexpected passenger, he then directs his dusty Suzuki hatchback down the highway. The deafening sounds of a passing cargo train mute the impact of a surprising revelation. This was to be his first visit to Chacabuco since 1973, when he worked there and in other sites as a nineteen-year-old military conscript and guard for the recently installed military dictatorship of General Augusto Pinochet. For good reason he does not know of Zaldivar. "We were threatened with being shot if we got too close to the prisoners," he explains as he drives up the dirt entrance road lined by barbed-wire fencing framing turned-up mounds of whitish-gray earth.

"It's strange to be here," he says, as he begins to point out familiar landmarks. "And I don't like it. Who knows how many people have disappeared, and also, it's not beneficial to go back to the way things were, to your memories."

He stops at the entrance long enough to share a cigarette and departs.

For travelers who decide to enter through the wood and wire gates of Chacabuco, it has been Roberto Hernan Zaldivar Varela's life experiences that consistently offer the richest singular picture of the dual history of Chacabuco, whether Zaldivar himself is present or his protege, Pedro, is there to guide visitors.

Homage to Zaldivar's role in communicating the multifaceted legacy of Chacabuco fills internet sites, documentary films, and covers the walls of his simple living quarters near the entrance of the camp. Pedro conveys reverence for Zaldivar, his "companero," attempting to render faithful versions of Zaldivar's spirit even when the older man is absent.

But for most of the last sixteen years Zaldivar has been at Chacabuco's gate to greet and play host as a guide, storyteller, educator, and guard over the rich cultural oasis in the seemingly barren landscape.

Born in Antofagasta, Zaldivar accompanied his parents as they worked the region's nitrate camps in his youth. Then, as an organizer in neighborhood groups, his church, and within leftist political parties, he was rounded up by the Chilean military and placed in the detention camp in Chacabuco in 1973, where he stayed for four months. He was in his early forties.

In 1992, three years after the return to democracy in Chile, Zaldivar returned to the Atacama's dry winds, baking sun, cold nights, and the infamously hard, encrusted earth called caliche, which has preserved the physical legacy of Chacabuco. Zaldivar has taken care of the cultural legacy.

Originally built for the mining and refining of nitrate, Chacabuco had a second life as one of the largest concentration camps of the Pinochet dictatorship, and then was later used as an advance camp for the storage of arms and general resources for a potential attack arising from border conflicts...