Where should I eat in Atacama Desert, and which local food or drink is worth trying?

Chile's National Institute of Industrial Property records the Limón de Pica as the country's first registered geographical indication, granted in April 2010, with the use of the name authorized to the Cooperativa Agrícola Pica Ltda. The protected zone is the Oasis de Pica, in the Tamarugal sector — the northern reaches of the Atacama, a long way from San Pedro, but the clearest illustration of how this desert farms: not across a landscape, but inside a handful of spring-fed pockets. The small, thin-skinned lemon is the base of the local pisco sour, and the registration exists because the name had commercial value worth defending.

That oasis logic governs eating everywhere in the desert. Produce arrives from irrigated strips along the few watercourses, or by road from far away; nothing grows between them. San Pedro de Atacama is the practical base, because the protected areas around it offer no alternative — Chile's tourism board is explicit that visits to Los Flamencos are daytime only, with no overnight stays and no camping, and that its high-plateau lagoon sectors are reached out along Ruta 23. Every meal is a town meal.

Pica is a cultivated patch in the Tamarugal, and its lemon exists because groundwater surfaces there and nowhere nearby — the same geography that makes the Atacama's green places look pasted onto the gravel rather than grown out of it.

A Chilean geographical indication is not a quality award; it is a legal boundary around a name. Because the Limón de Pica designation is tied to that one oasis and licensed to a named cooperative, a lemon described by that name should trace back there. It is a useful thing to know in a region where almost everything on a restaurant list arrived by truck.

• Midday — Eat in San Pedro. There is nowhere to eat inside the reserve sectors and nowhere to stay.
• Before an excursion — Reserve sectors are separately ticketed and daytime-only, so plan food around a return to town rather than a picnic at altitude.
• Evening — Ask what the lemon in the pisco sour is; Chile's first protected name is a desert product.

The CDC's food and water guidance puts raw or undercooked meat, fish, shellfish and eggs, unpasteurized milk and dairy, salads and uncooked vegetables, and raw unpeeled fruit in its higher-risk group, along with food from street vendors and restaurant food held without good refrigeration. It notes that tea and coffee made with freshly boiled water are generally safe, and that where soap and water are unavailable an alcohol-based sanitizer should contain at least 60 percent alcohol — while adding that sanitizer works poorly on visibly dirty hands and is less effective against Cryptosporidium and norovirus. At desert altitude the CDC separately advises limiting alcohol during the first 48 hours, which is worth remembering before a second pisco sour on arrival day.

The things-to-do question in this chapter covers Quitor and the reserve sectors you will be returning to town from, and the seasonal question explains why January and February are the months to avoid.