The project is located near Huan River, Hubei. The building has a circular layout with men and woman’s public toilets listed on both sides of the entrance square. There are only one dry latrine with poor sanitation condition, designer decided to take preserving these pine trees as the first choice. Thus, two annular buildings of different sizes were designed. These special characteristics of red brick are also used to build holes like flower puzzle, in order to create variable light and shadows,which creates dramatic and dynamic space effect combined with shadow of circular inner courtyard.