Playwright, producer and author Garnet Holme was induced by John Catlin and “Dad” O’Rourke to undertake a dramatic production in the natural amphitheater on Mount Tamalpais. At about 2000 ft. elevation, the view is spectacular: Mount Diablo and the Pacific Coast range 100 miles away. He chose Abraham and Isaac for the first production in 1913. The only way to reach the amphitheater was by hiking trails. Hardy hikers attended, and sat on the ground. It was such a success that the “Mountain Play Association” was formed to promote an annual play in this new Mountain Theater. The official play of the association became Tamalpa based on an old Indian legend of Mount Tamalpais. It was first performed in 1921, and seven more times from 1923 to 1970. It would not be until the late 1930’s that the audience would sit on serpentine rocks instead of on the ground. Under the direction of the landscape architect, Emerson Knight, enrollees of the Tamalpais Civilian Conservation Corps installed the rocks. His conception was to adapt the natural amphitheater into a structure more comfortable for human use, and to use indigenous stone and native plant material found on the mountain.