Cushing Memorial Amphitheatre, Open-air theatre in Mount Tamalpais State Park, United States.

The Cushing Memorial Amphitheatre is a 4,000-seat open-air venue in Mount Tamalpais State Park, Marin County, California, about 2,000 feet above sea level. The Civilian Conservation Corps built it in 1933 from massive serpentine rocks, with stone seating set into the mountainside.

The stone structure was built in 1933 by the Civilian Conservation Corps and named after Sidney B. Cushing, who was closely linked to the railway that once ran up the mountain. The tradition of performing theatre on this spot began 20 years earlier, in 1913, before any permanent structure existed.

The spring Mountain Plays have been staged here since 1913, when John C. Catlin, first president of the Mountain Play Association, financed the first production. Early audiences reached the natural amphitheatre by hiking or riding the Mount Tamalpais and Muir Woods Railway. The annual theatre season continues on the stone terraces.

The amphitheatre is reached on foot from a nearby parking area, and the uneven terrain makes sturdy shoes a good choice. At this elevation, temperatures can drop and wind can pick up quickly, so bringing a layer is wise even on warm days.

In 1967, this site hosted the Fantasy Fair and Magic Mountain Music Festival, one of the first large outdoor rock festivals in the country, held a week before the better-known Monterey Pop Festival. It brought together tens of thousands of people on a remote mountainside in a way that had never happened here before.