JOURNEY THROUGH THE CENTER OF THE EARTH

On May 24, 1869, John Wesley Powell began an expedition that would take him from Green River, Wyoming, to the 2 billion-year-old depths of the Grand Canyon. He was the first to run the Colorado River, but hardly the last. One hundred fifty years later, thousands of thrill-seekers, including Adam Schallau, make the journey every summer.

A PORTFOLIO BY ADAM SCHALLAU A sudden downpour from a monsoon storm creates numerous waterfalls in the Grand Canyon's Lower Granite Gorge. This location is near Mile 164 of the Colorado River's 277-mile run through the Canyon. "This is one of those photos that bring back very strong memories," photographer Adam Schallau says. "The Canyon transformed so quickly - from being warm and dry to being this dynamic environment - and we watched it over a matter of minutes. It was a surreal experience."

GRAND CANYON RIVER GUIDES

Taking a trip down the Colo-rado River through the Grand Canyon is one of the best ways to enjoy the beauty of the natural wonder. Preserving that beauty and experience is the mission of Grand Canyon River Guides. Formed in 1988, the association works to preserve and protect the Canyon and the Colorado through education and advocacy. The nonprofit group is made up of more than 1,700 members who have varying relationships to the Canyon, but share a passion for protecting it and its surrounding areas. The group's magazine, Boatman's Quarterly Review, highlights the history and issues concerning the Canyon and the river. “Our philosophy is that if people understand, then they will care,” says Executive Direc-tor Lynn Hamilton. “If they care, then they will defend.” For more information, call 928-773-1075 or visit www.gcrg.org.

"The Grand Canyon ... is a land of music. The river thunders in perpetual roar, swelling in floods of music when the storm gods play upon the rocks and fading away into soft and low murmurs when the infinite blue of heaven is unveiled. With the melody of the great tide rising and falling, swelling and vanishing forever, other melodies are heard in the gorges of the lateral canyons, while the waters plunge in the rapids among the rocks or leap in great cataracts. Thus the Grand Canyon is a land of song. Mountains of music swell in the rivers, hills of music billow in the creeks, and meadows of music murmur in the rills that ripple over the rocks."

JOHN WESLEY POWELL MEMORIAL MUSEUM

If you visit Lake Powell, make a stop at the John Wesley Powell Memorial Museum in Page to learn more about the man for whom the lake is named. John Wesley Powell was a Civil War veteran who, in 1869, set off down the Colorado River to discover the unknown. Three months later, the one-armed war hero and five other men emerged from the depths of the Grand Canyon at the mouth of the Virgin River. Powell helped discover and document many features of the Canyon and the Colorado that people enjoy today. The Powell Museum opened a century after that pivotal expedition, and now houses details of Powell's expeditions, as well as memorabilia that celebrates the history of Page and the Colorado Plateau. It also pays homage to the area's cultural history with exhibits of Native American artifacts. For more information, call 928-645-9496 or visit www.powellmuseum.org.The Colorado rushes past prickly pear cactuses in the Canyon's Inner Gorge at sunset. "One of my takeaways from this photo is something you can't see in the photo: the heat radiating from the rocks," Schallau says. "You really feel that in the Inner Gorge, because the dark rocks absorb all that heat. And I love the little bend the river makes at the end. It leaves you wondering what's around the corner." AH