SAN FRANCISCO — One of the men making a grueling ascent of a half-mile of exposed granite in California's Yosemite National Park is now just 1,000 feet from finishing the groundbreaking climb.

Tommy Caldwell climbed to a ledge 2,000 feet up on Thursday, says Tom Evans, a photographer and climber who has been chronicling the journey.

Caldwell and Kevin Jorgeson are relying completely on their physical strength and dexterity to make their way up the Dawn Wall, a vertical face on one side of El Capitan. Caldwell could become the first to accomplish the feat.

Jorgeson has been struggling to get past a particularly difficult section lower down and will try again Friday. The men have been climbing toward the 3,000-foot summit for two weeks.