Dumbleyung Lake is a large, shallow lake located in the Dumbleyung Shire of Western Australia. It covers an area of approximately 20 square kilometers and is known for its unique shape and rich biodiversity. The lake is a significant habitat for various bird species, making it a popular spot for birdwatching. The lake is also historically important, as it was the site of the first successful flight of a heavier-than-air aircraft in Australia by John Duigan in 1910. Today, Dumbleyung Lake attracts visitors for recreational activities such as fishing, kayaking, and picnicking, contributing to the local tourism economy.