Because scientific studies, nowadays we know that before the eruption of 1968 the volcano was dormant for almost 500 years. Its last eruptions had been close to 1525. Based on this considerable time without any activity, the Volcano began to accumulate pressure internally, which culminated with the big eruption on 1968.
Settlers from the volcano west site called "Pueblo Nuevo" could do almost nothing to save them from such a titanic eruption that destroyed 7 kilometers all around. 87 countrymen died on this eruption. It was an emergency for the whole northern part of the country. All nearby area of Arenal was declared like high volcanic risk and for this reason, many people of that time left the region and some decided to sell their lands very cheap.
Some years later, at the end of 70's, some foreigners began to realize that there was a magnificent volcano in the north of Costa Rica, and little by little the arrival of visitors started to increase. By the 80's, tourism in La Fortuna was developed more and more to become what it is nowadays "one of the most important tourist towns in the country".
At the West side of the volcano we can find the Arenal Lake; it is the largest lake in all Costa Rica. This lake owns an area of 87 square kilometers. At the East side there is La Fortuna town which is the most important tourist center of the region. Finally we can find at the South part of the volcano the mountains of Cerro Chato, Los Perdidos and others that are part of the Tilarán volcanic mountain range.