Since the end of Los Chocoyos, continuing volcanic activity has built three volcanoes in the caldera. Volcán Atitlán lies on the southern rim of the caldera, while Volcán San Pedro and Volcán Tolimán lie within the caldera. San Pedro is the oldest of the three and seems to have stopped erupting about 40,000 years ago. Tolimán began growing after San Pedro stopped erupting and probably remains active, although it has not erupted in historic times. Atitlán has developed almost entirely in the last 10,000 years and remains active, its most recent eruption having occurred in 1853.