By the early 20th century, the rock was known as Big Rock. With the Miller family's permission, members of Seattle's Mountaineers Club practiced their rock climbing techniques there. Edmond S. Meany, president of Mountaineers and a professor at the nearby University of Washington brought his students to the rock to learn about glacial movement and land forms. Later, Boy Scouts also learned to climb there, taught by German-born climber and scout leader Wolf Bauer. REI founder Lloyd Anderson taught Mountaineers and Boy Scouts at the rock. Among the prominent climbers whose training started at Big Rock were German-born Fred Beckey and Jim Whittaker, who became the first American to reach the top of Mount Everest.