Yan ChauYan Chau is an islet in the North District in the New Territories of Hong Kong. It is located within Double Haven.ConservationYan Chau is part of the Double Haven Special Area that covers and was designated in 2011. The special area includes the islets Pak Ka Chau, Yan Chau as well as the islet of Ap Lo Chun and a part of Ap Chau. The geology of the area is characterised by sedimentary rocks of the Jurassic and Cretaceous periods.