Sport: Mounting the Diamond

They call it "the Diamond"—a 1,000-ft. slab of granite that slants out from the mountainside like a giant teetering tombstone, and guards the eastern approach to Longs Peak, a 14,256-ft. tower in the Rockies some 75 miles northwest of Denver. The stretch of rock is one of the last great unconquered climbs in the U.S.* Last week a pair of seasoned climbers from California checked their gear and set out to become the first men to mount the Diamond.

For two hours Dave Rearick, 28, a Ph.D. in mathematics from Caltech, and Bob Kamps, 26, a fourth-grade teacher in North Hollywood, stood...