El Tatio is one of the defining experiences of the Atacama Desert. At 4,320 metres above sea level, it is the highest geyser field in the world, with over 80 active geysers and 60 hot springs spread across a broad volcanic plain. The standard approach is a pre-dawn departure from San Pedro — about 90 minutes of driving up a rough road in the dark — to arrive at first light when the steam columns are at their most spectacular against the cold morning sky.
The scene at sunrise is extraordinary: dozens of columns of white steam rising from the flat ground, some only knee-height, others reaching 6–8 metres, the surrounding volcanoes catching the first sunlight, and the temperature well below zero. The site has a swimming area in one of the hot springs, which is genuinely popular — climbing into warm geothermal water when the air temperature is -5°C is a memorable experience.
Tour operators in San Pedro offer this excursion with departures around 4am. The altitude at El Tatio is serious — 4,320 metres means some visitors experience altitude sickness. It is not recommended as a first stop if you arrived in San Pedro the previous day; allow at least one full day in town to acclimatise first.