The brink of the crater does not resemble any of the other volcanoes I have visited, such as Vesuvius, Jorullo or Pichincha. On the peak the wall, which surrounds the crater like a parapet, is so high that it would not let you reach La Caldera were it not for a breach on the eastern side caused by a very ancient lava overflow. We climbed down through this gap to the bottom of the elliptical funnel.