These are factors that impact the nature of the world from the highest mountain peak to the deepest ocean trench.

CNN: An SOS on World Oceans Day: Save our seas, save ourselves

The avalanche on the western side of the mountain, America's highest peak, was first thought to have occurred on Thursday, the parks service said Sunday.

CNN: Avalanche recovery efforts suspended on Mount McKinley

The mountain's highest peak is the Guagua ("child" in Quechua), a two-hour hike from the town of Lloa, a one-hour drive south-west of Quito.

BBC: Scaling the Ecuadorean Andes

In summer months, it is possible to hike to the peak of Qornet as-Sawda, Lebanon's highest mountain.

BBC: Lebanon in a week: The ultimate road-trip guide

This is already a worry, for example, on Mount Fansipan, Indochina's highest peak, where uncontrolled tourism is degrading the top of the mountain.

ECONOMIST: Tourism could do a lot of good if Vietnam handles it properly

Noguchi climbed his first mountain, Mont Blanc, at age 16 before becoming the youngest person to climb the highest peak on each of the seven continents.

CNN: Ken Noguchi: Scaling environmental heights