Cowan Creek is a significant tidal waterway nestled within Ku-ring-gai Chase National Park, flowing as a major tributary into the Hawkesbury River system north of Sydney, New South Wales. The creek is flanked by high hills and steep sandstone cliffs that define the landscape and create a naturally sheltered environment, making it a reliable destination even when strong winds batter the surrounding region. The waterway forms part of the boundary between Hornsby Shire and Ku-ring-gai Municipality to the west, and Pittwater and Warringah to the east. As an estuarine system connected to the Hawkesbury River and ultimately Broken Bay, Cowan Creek offers a diverse and productive fishery in a stunning national park setting.