Built in the 1920s, the garden includes a traditional Japanese tea house and the historically significant One-Mat Room constructed out of wood gathered from sacred and historic sites throughout Japan. ICU owns a 240-acre (0.97 km2) campus in Nasu and a 13-acre (53,000 m2) retreat center in Karuizawa, Kitasaku District, Nagano Prefecture. ICU houses a Rotary Center for peace and conflict resolution, partnering with Rotary International.