[PIF]

For more information, pictures, and history see Mayon Volcano. Fortunately this volcano eruptive history only reached a Volcanic Explosivity Index of 4 twice, with most eruptions in the range of 1-3. St Helens was a VEI of 5, Pinatubo was 6. (The VEI scale uses factors of 10 - Pinatubo was 10 times greater than St Helens.)

[Pontiac]

Thanks for the link.

That is about as perfect a volcano cone as I have seen.

A terrible beauty.