Sourced from Wikipedia:
El Tatio is a geyser field located within the Andes Mountains of northern Chile at 4,320 meters above mean sea level. Contrary to some reports, it is not the highest-elevation geyser field in the world. Puchuldiza Geyser Field, Chile, and possibly several other fields are higher in elevation. Tourists often visit the geysers while touring the nearby Atacama Desert and the village San Pedro de Atacama. “With over 80 active geysers, El Tatio is the largest geyser field in the southern hemisphere and the third largest field in the world, after Yellowstone, USA, and Dolina Giezerov.
This was a wonderful tour we did in combination with Cactus Valley which included cacti and hot springs. It’s starts very, very early in the morning, and when you arrive at the geyser field it’s freezing, but as the sun rises, it will warm up. And later in the day you will be swimming in hot springs. We paid for a tour from Cactus Tours.