The unusual thing about the Arenal volcano is that it did not blow from the top. The lower explosions in 1968, created a domino effect up the mountain as pressure continues to build.
Today, the continued activity inside the volcano has resulted in the second peak actually rising higher than the first.
Most days the clouds hang low hiding a significant portion of the mountain. Today, just for a few minutes the sun broke through and the clouds burned off so we could glimpse the twin peaks.