Duo Tommy Caldwell and Kevin Jorgeson completed a historic climb in California on Wednesday, reaching the summit of the 3,000-foot rock known as El Capitan in Yosemite National Park using only their hands and feet. The ascent marks the first free climb of one of Yosemite's most difficult challenges, the Dawn Wall. The pair arrived just after 6 p.m. and were greeted by family, friends and a group of reporters after 19 grueling days of climbing. The Dawn Wall has long been regarded as too steep and lacking enough cracks for a free climb. "This is not an effort to 'conquer,'" Jorgeson tweeted Tuesday from 2,000 feet. "It's about realizing a dream."