Today, the Cagsawa Ruins is a tourist site and a grim reminder of Mount Mayon's danger.

WSJ: Philippines Volcano Spews Ash, Kills 5

Climbers are required to seek permission from government agencies before they climb Mount Mayon.

WSJ: Philippines Volcano Spews Ash, Kills 5

Mount Mayon has erupted 48 times, with the last time being in 2009.

WSJ: Philippines Volcano Spews Ash, Kills 5

Five days after Mount Mayon erupted, all were grounded because of safety fears.

ECONOMIST: No disaster in the Philippines

If the official machinery for responding to disasters worked at Mount Mayon, it was partly because there was plenty of warning.

ECONOMIST: No disaster in the Philippines

Institute Director Renato Solidum said the explosion early Tuesday was "steam-driven" and is considered "normal" activity for a volatile volcano like Mount Mayon.

WSJ: Philippines Volcano Spews Ash, Kills 5

He said he would still climb mountains, but not Mount Mayon.

WSJ: Guides Recall Escape From Philippine Volcano

Mr. Mabao was 16 when he started guiding tourists up Mount Mayon and is a member of the Panaway Mountaineer Group, which usually climbs the 2, 440-metervolcano three to four times a week.

WSJ: Guides Recall Escape From Philippine Volcano

Mr. Mabao was 16 when he started guiding tourists up Mount Mayon and is a member of the Panaway Mountaineer Group, which usually climbs the 2, 440-meter, or 8, 000-foot, volcano three to four times a week.

WSJ: Guides Recall Escape From Philippine Volcano