Even later, several mafic centres grew southwest and west of the Antofalla complex. Fumarolic activity continues to this day, the existence of geysers was reported in 1962 and traces of an extinct geyser such as sinter structures have been found at Botijuelas. There are reports that the main volcano smoked occasionally such as in 1901 and 1911 and Antofalla is sometimes incorrectly considered the highest active volcano in the world, but the Global Volcanism Program considers the complex as Pleistocene in age, and no clear evidence of Holocene activity is found.