Hello, we will spend one day in Guangzhou.

We have already visited the city a few times and have been to Baiyun Mountain, Yuexiu Park, Beijing Road, Shamian Island, and around the Sacred Heart Cathedral. What other not-so-popular attractions could we visit? We'd prefer something outside where we can walk and perhaps see older parts of the city, not areas that have been already modernized and not a theme park.
Thank you