The main house on the Shadelands Ranch is a 1903 redwood-framed Colonial Revival structure that showcases numerous historical artifacts, many of which belonged to Hiram Penniman. The museum acts as home to a collection of historical documents, newspapers, photographs and government records related to Contra Costa County and Walnut Creek. The grounds are available for rent. Visit the museum's Web site to see what local and holiday events are being scheduled for the public, or stop in for a tour.