Ernst Nature Theatre was designed by the internationally acclaimed landscape design firm the Olmsted Brothers of Brookline, Massachusetts, and was built into the landscape as an outdoor performance space in 1921. The brothers were co-founders of the American Association of Landscape Designers. Local craftsmen, including Cephas A. Burns, an African American master stonemason, built the theater under the direction of President William Waddell Boyd. Its inaugural play was presented at the Tree Day celebration in 1922, continuing a tradition initiated by President Leila McKee in 1890. On June 8, 2024, after improvements funded by Western donors, the Western College Alumnae Association, Inc. rededicated the theater during the organization's final reunion on the Western Campus.