A tourist poses for a picture along the crater of the Cerro Negro volcano, one of the most active in Nicaragua, before volcano surfing down its slopes in Leon, about 120 kilometers northwest from Managua July 23, 2012. [Photo/Agencies]

Antony of a tour company gives instructions to tourists as they prepare to volcano surf down the slopes of the Cerro Negro volcano, one of the most active in Nicaragua, in Leon, about 120 kilometers northwest from Managua, July 23, 2012. [Photo/Agencies]