Toba is a large lake, in the middle of the northern part of the Indonesian island with a surface elevation of about 900 m. The Toba eruption occurred at what is how Toba Lake about 4000 years ago. It had an estimates volcanic explosively index of 8, make it possibly the largest volcanic eruption within the last two million years, because this is the interest tourist attraction that why we should to talk about Toba eruption.