The 100th Anniversary Of Alaska's Valley of Ten Thousand Smokes (PHOTOS)

The state of Alaska is preparing for the centennial of massive volcanic eruptions that changed the global climate, spawned acid rain and buried the Ukak River Valley in June 1912.

Now protected as Katmai National Park and Preserve, the volcanically active area includes the so-called Valley of Ten Thousand Smokes, named for the literally smoking cracks and fissures that early explorers found in the wake of the eruption.

Today's visitors to the region, which lies about 300 miles from Anchorage, can participate in all the usual National Parks activities, like ranger-led hikes, wildlife viewing and other outdoor pursuits, though the smoking fumaroles have since closed up.

Elsewhere this summer, the Alaska Public Lands Information Center will hold a series of talks on the significance of the area and its geology, and the park will screen in Anchorage this September a documentary about the valley commissioned for the centennial.

Here's a look at the impressive landscape of the valley, which was first explored by botanist Robert Griggs under the auspices of the National Geographic Society in the late 1910s.