This Month in Photo of the Day: Adventure and Exploration Photos

A volcanologist strides through a murky expanse of steam on Mutnovsky Volcano during an expedition to Kamchatka, Russia. The steam billows from a fumarole, or a vent created by heated groundwater and rising volcanic gas, and it serves as a visible reminder that the peninsula is one of the most volcanically active regions in the world, with some 29 active volcanoes.

Explore Kamchatka »
See pictures of National Geographic explorations »
See more pictures of volcanoes »