The Colorado Springs School (CSS), on the estate formerly known as Claremont, is a private, nonprofit, college preparatory school serving pre-kindergarten to 12th grade in Colorado Springs. The 32-acre campus is located on the former Claremont Estate, built in 1907 as the home of Charles and Virginia Baldwin. The main building, known as the Trianon (formerly called "Claremont"), is listed on the National Register of Historic Places.