Bubbling.
kallerna — CC BY-SA 4.0 · kallerna — CC BY-SA 4.0 · kallerna — CC BY-SA 4.0 · kallerna — CC BY-SA 4.0
A broad field of volcanic activity at about 4,900 metres, whose Spanish name means «morning sun», where columns of steam rise from vents in the ground, pools of grey and brown mud boil with endless bubbles, and the ground around them is stained yellow, orange and red by sulphur and minerals. Visitors usually arrive at dawn on the second or third day of the Uyuni tour, when the steam is thickest in the cold air, the smell of sulphur fills the place and the first light colours this strange, otherworldly scene. Most of the field has no paths or barriers, the ground around the pools is thin and can collapse, and the water and mud are boiling, so stay with your guide on firm ground and keep away from the edges. It is one of the tour's highest stops; the air is thin and the dawn cold intense. It is seen on 4x4 tours from Uyuni, most often the three-day tour, so choose a company with careful drivers and sound vehicles. The altitude is over 4,000 metres and nights are bitterly cold, often below minus ten, so bring winter clothes and a warm sleeping bag.
Bubbling.
At dawn.
Sulphur and minerals.
Eduardo Avaroa reserve, south of Laguna Colorada
Dangerous if you leave firm ground, as the mud boils and the ground around pools is thin, so stay with your guide and away from edges.